Was the Last Supper not the Passover meal?

Question: The accepted answer on How long was Jesus in the tomb? would only have been possible if the Last Supper was not the Passover meal, which I had always thought it was.  Was the Last Supper in fact not the Passover meal?
Comment: @PeterTurner  in his book, he aligns with John's timeline; that is, the Passover for them was yet to be (Christ suffered/died before Passover).  So, the Pope believed the Last Supper was not the Passover meal.  Incidentally, the Pope's view is a complete reversal of the Catholic Church belief over the previous 1,900 years.  Pope Leo must be saying ... no way!
Comment: Pope Benedict XVI posits that it wasn't in volume 2 of Jesus of Nazareth. I don't know the rationale though (not taught ex cathedra though)
Answer: Two things are clear from scripture:

The "last supper" was in fact a passover meal. Multiple references in Mark 14, Matthew 26 and Luke 22 make it clear that the disciples prepared a passover meal. In Matthew Jesus says "I am going to celebrate the Passover with my disciples at your house." In Luke it reads "So they prepared the Passover. When the hour came, Jesus and his apostles reclined at the table.". Other elements of the meal are drawn directly from Passover practice. Clearly this was a Passover meal.
It is also clear that this was done on the day before Passover. John 18 and 19 indicate that it was "the day of preparation for the Passover".

There are a number of possible reconciliations of this. Some speculate that Jesus was a part of a minority Jewish sect that celebrated Passover on a different day. Others that he celebrated Passover a day early because he knew he wouldn't be able to do it on the right day (I don't know what Jewish Law would have said about that, but Jesus was never one to get hung up on legal technicalities).
Comment: What's the law if you're going to be unavailable next month? Like because you're going to be dead?
Comment: @DJClayworth: No, it is not **clear** that the Last Supper was a Pesach seder ("Passover meal"). If it was so "clear," we wouldn't be asking the question.
Comment: Jewish law would be to do it the following month, but that allowance was only for those unavoidably travelling on the day itself. I may remember that wrong. Probably worth asking on Judaism SE.
Comment: Actually, it wasn't done on a different day. According to God's and thus Jewish reckoning, a day begins at sunset (e.g. "the evening and the morning were the first day").  Jesus partook of the passover meal with his disciples after sunset, in the nighttime portion of the 14th of Nisan. They then went out, during the night, to the garden where He was taken prisoner. He was then tried and crucified during the daytime portion of the 14th.
Comment: I think I supplied references from three Gospels to indicate that it was a Passover meal. Do you have anything from the Bible to indicate that it wasn't a Passover meal? Note that I'm already aware that it was done on a different day, and that Jesus did things that wouldn't normally be done at a Passover meal. That's the point. It's how we treat those two facts that make this a lesson.
Comment: @DJClayworth: See my post.
Comment: Short and sweet. Not much detail, but still +1. My answer looks at the "minority Jewish sect" option.
Answer: My new understanding of the Last Supper is mostly based on the information at http://www.therefinersfire.org/celebrating_passover.htm.
The key verses which indicate that Christ was actually crucified on the day before the Passover feast are John 18:28 and John 19:14.

John 18:28 NIV
Then the Jewish leaders took Jesus from Caiaphas to the palace of the Roman governor. By now it was early morning, and to avoid ceremonial uncleanness they did not enter the palace, because they wanted to be able to eat the Passover.
John 19:14 NIV
It was the day of Preparation of the Passover; it was about noon.
"Here is your king," Pilate said to the Jews.

The day of preparation would be when they slaughter the Passover lamb, which would then be eaten that night.
Answer: Jesus entered Bethany six days before the Passover (John 12:1).  I believe John is referring to the Passover Seder on the 15th of Nisan.  That would make Jesus there on the 9th of Nisan.  Then the next day He entered Jerusalem (John 12:12) on the 10th of Nisan (Palm Sunday).  The multitude acknowledged Him as the Messiah and shouted "Hosanna![d]" (save now) "Blessed is he who comes in the name of the Lord!"[e]"Blessed is the king of Israel!"  In doing so they were also choosing Him as the True Lamb of God, on the same day as lambs are chosen for the Passover Seder.
He was examined for 4 days (10th, 11th, 12th and 13th of Nisan) (Sunday, Monday, Tuesday and Wednesday) just like all Passover Lambs were examined for four days to make sure they were without spot or blemish.  He was tested over and over by being asked question after question and they could not find any fault with His answers.
I believe the Last Supper was early on Thursday (by the Jewish day) the 14th of Nisan.  Probably shortly after sundown, which began a new day.  It was a Passover Meal, but it was a day earlier than the normal Passover Seder.  God allows exceptions for good reasons, see Numbers 9:6-11 and II Chronicles 30:2-15.  Jesus knew that He was going to die late on the 14th of Nisan as the True Lamb of God.  Therefore, He would not be able to celebrate it on the 15th Nisan.  In Luke 22:14 we read   14 When the hour came, Jesus and his apostles reclined at the table. 15 And he said to them, "I have eagerly desired to eat this Passover with you before I suffer.  And by having it a day early He was able to institute the Holy Communion which we cherish.
Then here is some of what happened after the Last Supper that day, He went to the Garden of Gethsemane to pray, was betrayed with a kiss, arrested, deserted and denied by those closest to Him, tried, struck, spat upon, had his beard pulled, tried again, mocked, crowned with thorns, scourged, made to carry His own cross, crucified, and entombed all done sometime before sunset on that Thursday the 14th of Nisan (the day I believe John refers to as the day of preparation for the Passover).  I believe He died on the cross just outside the walls of Jerusalem at the same time that the Passover Lambs were being slain inside the walls of Jerusalem.
Then Friday the 15th of Nisan was the First Day of Unleavened Bread, a Special Sabbath or John calls it a High Sabbath.
[Matthew 26:17, Mark 14:12 and Luke 22:7 are very confusing.  I believe they take place on Wednesday the 13th of Nisan.  Since the Passover Seder for Jesus and his Apostles was a day early, the killing of the lamb for them had to be moved forward one day.  Also The First Day of Unleavened Bread comes the day after the sacrifice of the Passover Lamb (Leviticus 23:4-8) however the day of the killing of the lamb commonly became known as the first of unleavened bread because it was the day they rid their homes of all leavening before the official start of the feast.]
Then the 16th of Nisan was the regular weekly Sabbath.
Then Jesus arose before dawn on the 17th of Nisan the first day of the week or to us Resurrection Sunday also the day of the Firstfruit Wave Offering.
(From Palm Sunday to Saturday in the tomb was 7 days, the number meaning complete, then Resurrection Sunday was the 8th day, the number for new beginnings.)
Comment: @Adam  not exactly; the Passover lambs were picked and inspected and if found with some sort of spot or blemish, then it was released and new one inspected.  Jesus was found without spot or blemish and was sacrificed.  They questioned until they shut up Mt 22:46
Comment: @Adam  I've reread this answer and don't see the idea Jesus was released.  Could you point this out?
Comment: This answer makes the claim that the lamb was set free after the 4 days of investigation...i do not find any evidence to support such a theory. There is no evidence Jesus was let go after he was questioned and then re arrested again during the middle of the night whilst in the garden of Gethsemane. This theory is deeply flawed!
Comment: And if no defect was found, then it was not released right? So how then is your claim even supported, because Jesus wasn't released. Where is your reference to support him being released.
Answer: Was the Last Supper not the Passover meal?
Before answering this it is necessary to lay some background.
It is entirely critical to get the correct day of crucifixion before attempting anything else: until you have the day of crucifixion you cannot tell whether the Last Supper was a Passover meal according to the Conventional Jewish Calendar of the time.
The 14th Nisan was the day the Passover lambs were sacrificed starting in the afternoon. Andrew Steinmann claims the day when the Passover [lambs] were prepared was on the 13th Nisan to eat in the evening, i.e. to eat on the fourteenth, ("From Abraham to Paul – A Biblical Chronology", page 278).  With respect to him and his very important book, this is not correct for three reasons:
Firstly, at the Passover meal, leavened bread could not be eaten.  Even today, leaven must be removed from the houses, hotels, etc. on the morning of the 14th (see Wikipedia: Removal of chametz).  If they ate the Passover meal on the evening following the 13th (i.e. on the 14th after the sunset closing the 13th) then they would eat the Passover before they had removed all the leaven!
Secondly, it was the 15th which was called the first day of the Feast of Unleavened Bread:

The feast of Unleavened Bread succeeds that of the Passover, and falls on the fifteenth day of the month, and continues seven days
(Josephus, Antiquities, chapter 10, section 5).

But if the Passover meal was eaten after the sunset closing the 13th, then why was the 14th Nisan not called the first day of Unleavened Bread?  Furthermore, what could they eat during the daylight hours of the 14th?  Not leavened bread, because they had already started eating unleavened bread.
The Passover meal was usually finished before midnight, though it could be eaten anytime before morning light. It makes absolutely no sense that there should be a gap of 18 hours from 12 midnight 14th Nisan to the beginning of 15th Nisan at sunset 6 pm, i.e. between the usual end time of the Passover meal and the earliest possible time for the beginning of the week of Unleavened Bread.  Such a gap could not possibly represent any feature of the escape from Egypt.
Thirdly and most significantly, it is the testimony of all that the sacrifice of the Passover lamb was made on the afternoon of the 14th Nisan.  These are the testimonies:-

Of Josephus, in Antiquities chapter 10:

In the month of Xanthicus, which is by us called Nisan, and is the beginning of our year, on the fourteenth day of the lunar month, when the sun is in Aries, [for in this month it was that we were delivered from bondage under the Egyptians,] the law ordained that we should every year slay that sacrifice which I before told you we slew when we came out of Egypt, and which was called the Passover; and so we do celebrate this Passover in companies, leaving nothing of what we sacrifice till the day following.

Of Philo:

(149) And this universal sacrifice of the whole people is celebrated on the fourteenth day of the month, which consists of two periods of seven, in order that nothing which is accounted worthy of honour may be separated from the number seven.

And of the Talmud Pesachim 108a:

"As ben Beteira maintained that when the Torah says the Paschal lamb must be sacrificed "bein ha'arbayim" (Exodus 12:6), which literally means: Between the evenings, but is often rendered: In the afternoon, the term refers to any time between the evening of yesterday and the current evening of the fourteenth." (See Sefaria: Pesachim 108a)

So the Passover meal was eaten after the sunset of the 14th Nisan i.e. on the 15th Nisan.
The first fruits
Our Lord rose from the dead and appeared on Sunday as the first fruits of them that slept after the Sabbath Day (1 Corinth 15:20, Leviticus 23:11, Matt 28:1).
It is commonly said our Lord rose on "the third day" (Matt 16:21, Acts 10:40, 1 Cor 15:4).  In other passages it says "after three days" (e.g. Mark 8:31).  These two phrases must have the same meaning. Matthew 16:21 is from a parallel passage to the one containing Mark 8:31, recounting the time Peter said "Thou art the Christ", and yet Matt 16:21 uses "the third day" and Mark 8:31 uses "after three days".  The two phrases have the same meaning. (See also Genesis 42:17-18, Matthew 27:63-64).
What is important to remember is the Jews used "inclusive counting": our Lord was including the remainder of the day on which he was speaking as one day within the three-day count.
The meaning of "on the third day" and "after three days"
In Luke's Gospel, our Lord was told Herod wanted to kill him.  He replied

"Go ye, and tell that fox, Behold, I cast out devils, and I do cures to day and to morrow, and the third day I shall be perfected." (Luke 13:32)

Clearly, for the Lord Jesus and the Jews "the third day" signified the day after tomorrow.
The same meaning for "the third day" is found in Leviticus 7:15-17 where a peace offering must be eaten the same day it is sacrificed, a voluntary offering can be eaten the following day as well, but the remainder cannot be eaten the third day but must be burnt.  Again, "the third day" here means "the day after tomorrow".
Three days and three nights
Jesus said he would be in the grave for "three days and three nights" in Matthew 12:40.  This claim must harmonize with (the much more common phrase of) rising from the dead "on the third day", and "in three days" (John 2:19-20).
Maybe the Jews did not have a term such as a "24-hour day" to distinguish it from a "day" meaning the period of the hours of daylight and thus used the phrase "a day and a night" to mean a 24-hour day.
"Three days and three nights" is an idiomatic expression meaning a period including time from three consecutive 24-hour days.  It is similarly used in Esther 4:16, where the fast ended on the third day (Esther 5:1).  If the expression "three days, night or day" in Esther 4:16 were to be taken literally then the fast would have ended on the fourth day.

The Jerusalem Talmud quotes rabbi Eleazar ben Azariah, who lived around A.D. 100, as saying: "A day and night are an Onah ['a portion of time'] and the portion of an Onah is as the whole of it" (from Jerusalem Talmud: Shabbath ix. 3, as quoted in Hoehner, 1974, pp. 248-249, bracketed comment in orig.). Azariah indicated that a portion of a twenty-four hour period could be considered the same "as the whole of it." Thus, in Jesus' time He would have been correct in teaching that His burial would last " three days and three nights," even though it was not three complete 24-hour days.  (cf Hoehner, Harold W (1974), "Chronological Aspects of the Life of Christ—Part IV: The Day of Christ's Crucifixion," Bibliotheca Sacra, 131:241-264, July.)

The Jews counted the number of days in precisely the same way as they (usually) counted the number of years for the reign of a king: the reign length was the number of New Year's Days in his reign plus 1.  (This was not always their practice - sometimes they copied the practice of surrounding nations.)  So a king could have reigned for literally one year and two days, but if that contained two New Year's Days then the Jews recorded that he reigned for "three years".  This practice is found in the Old Testament and was made clear by Edwin Thiele in "Mysterious Numbers of the Hebrew Kings".
It follows from all that since our Lord rose from the dead on Sunday morning then he was crucified on Friday.  A Friday crucifixion makes "the day after tomorrow" a Sunday.  (I'm sorry but I cannot take seriously the suggestion that He rose from the dead after Saturday sunset and hid away (in the sepulchre?) until Sunday morning.)
It used to be a commonly held view that the date of the crucifixion was arrived at by assuming the Last Supper was a Passover meal and therefore was eaten in the evening after the lambs were sacrificed on the afternoon of the 14th Nisan. For example, William Hendriksen in his Commentary on the Gospel of John claims the Friday was on the 15th Nisan.  But Hendriksen et al. were relying on older inaccurate astronomical calculations.  Modern astronomical calculations confirm that the Friday at Passover for both AD 30 and AD 33 fell on the 14th Nisan.
Another problem with this is that the 15th Nisan was the first day of the Feast of Unleavened Bread and was itself a special Sabbath Day (Lev 23:7).  If the Friday was a 15th Nisan then it now seems to me disastrous for understanding John's account of the day of crucifixion, such as wanting to quickly bury our Lord because the next day was a Sabbath (John 19:31).  This is incomprehensible if the day of crucifixion itself was 15th Nisan and therefore itself a special Sabbath day.
But what if the Friday (daytime) was the 13th Nisan?  The problem with this is that the Sunday would then be the 15th Nisan and the first day of the week of Unleavened Bread, and the Sunday would then be a special Sabbath day or holy convocation and the women would obviously not have brought spices on that day. It would also mean that the first fruits wave offering would not be permissible until either the next day, Monday, or until the following Sunday after the weekly Sabbath which would have been the Sabbath during the week of Unleavened Bread (Lev 23:11).  (Depending on their interpretation of "sabbath" in Lev 23:11, some Jewish religious leaders in the New Testament era believed the wave offering of the first fruits needed to be after the special Sabbath/holy convocation (i.e. always on the 16th Nisan) and some believed it needed to be after the weekly Sabbath (i.e. after Saturday) which happened during the week of Unleavened Bread (i.e. always on the Sunday).)
In consequence, if Christ is truly the first fruits then he must have risen from the dead on the 16th Nisan, on the second day of the Feast of Unleavened Bread, the day after what it turns out was a High Sabbath (John 19:31), being both the weekly Saturday Sabbath day and a special Sabbath being the first day of Unleavened Bread, the 15th Nisan.
From the above reasoning, the only remaining possible option is that our Lord was truly, in terms of timing, our Passover Lamb, dying precisely during the time the lambs were being sacrificed on the afternoon of Friday 14th Nisan, and the first fruits of them that slept (1 Cor 15:20), rising from the dead on the second day of the Feast, the day after the Sabbath (Lev 23:11), on Sunday the 16th Nisan.
(Before continuing, I think it is worth meditating the wonder of this: that the day of our Lord's resurrection, because he died on a Friday which was the 14th Nisan, and rose on a Sunday which was the 16th Nisan, that none of the Jewish religious leaders, no matter what their interpretation of "sabbath" in Lev 23:11, could have objected to the Apostle Paul likening our Lord's resurrection to the first fruits offering, "the first fruits of them that slept" (1 Cor 15:20). And Friday plus 14th Nisan is the only possible combination for which this is true.)
The above argument means the Last Supper could not have been a Passover meal according to the Conventional Jewish Calendar, because the lambs had not yet been sacrificed.
The Mystery of the Last Supper
But the Last Supper was a Passover meal: this is clear from the synoptic gospels.  However, it was eaten before the lambs were sacrificed on the 14th Nisan (John 18:28).
How can this apparent contradiction be resolved?
Colin Humphreys in his book "The Mystery of the Last Supper", takes the reader right back to Moses and examines the calendar the Jews used in the OT.
In Egypt, the Egyptian Calendar had each month start on the day the moon disappears and the day starts at sunrise (because the last crescent moon is seen in the morning), i.e. about 2 days before the Mesopotamian style calendars. The only change to this calendar commanded to Moses on leaving Egypt was to change the first month of the year to the one of the spring equinox (Exodus 12:1-2). Humphreys argues this was the only calendar, the Mosaic Calendar, used by the Israelites/Jews right up to the Babylonian Captivity.
(To understand why Moses writes "and there was evening and morning", indicating each 24-hour day started at sunset, in Genesis chapter 1, it needs to be realized that the first few chapters of Genesis originated, not with Moses, but in Mesopotamia (where the day began at sunset).  Moses incorporated inspired scripture which had been written earlier by someone in Mesopotamia. See Who documented biblical events before Moses? for details.)
During the Babylonian Captivity, it was the elite and the nobility (or their children) who went into Babylonian Captivity.  The poorer Jews were left in the land of Judaea.
The Babylonian Calendar was different to the Egyptian Calendar, and the Mosaic Calendar.  For the Babylonians, the first day of the month was the day of the first sighting of the new crescent moon in the evening.  For the Babylonians the new day and date change was at sunset (because the new crescent moon is seen in the evening), and the month started about two days later than the Egyptian and Mosaic Calendars.
The Jewish elite in Babylon adopted the Babylonian Calendar as their own.  When they came back after the Babylonian Exile they brought back the new Calendar.  But for the more ordinary Jews who had not been taken to Babylon but remained in Judaea and Galilee, a significant number of them retained the Mosaic Calendar.
After the Babylonian Exile there thus existed in Judaea two different calendars where the date of each day differed by about two days each month - the difference in days being the difference between the disappearance of the old crescent moon and the appearance of the new crescent moon.
The Temple, ruled by the elite, used the Babylonian-influenced calendar.  People such as the Galilean fisherman, and maybe most in Galilee, used the Mosaic Calendar.
And yet everyone sacrificed the Passover lamb on the 14th Nisan and ate the Passover meal after sunset according to their own calendar.   The upshot of all this, according to Colin Humphreys, is that our Lord Jesus ate the Passover on the day of the month instituted by Moses, but the Temple and most of the Jews sacrificed the lambs and ate the Passover two days later.
So, taking AD 33 as an example, for the Temple and most of the Jews, the 14th Nisan was on Friday when the lambs were to be slaughtered; but for our Lord Jesus and many others the 14th Nisan was on Wednesday of the same week.  He and his disciples celebrated the Passover meal which was the Last Supper according to their Mosaic Calendar in the evening of Wednesday (which for them was still 14th Nisan).
(You can check for yourself online that the last appearance of the old crescent moon was on Wednesday morning 18th March AD 33 at "The Jewish Calendar" by Rita Gautschy: and so the moon did not appear on Thursday morning making it 1st Nisan: this would make Wednesday 1st April the 14th Nisan, during the afternoon of which the lambs were killed according to the Mosaic Calendar, and the Passover eaten after sunset which was still 14th Nisan.)
Our Lord was arrested in the night and early hours of Thursday, and finally crucified on Friday morning, which was the 16th Nisan in the Mosaic Calendar, but the 14th Nisan in the Majority Calendar, and died at the time the majority of the lambs were being slaughtered on Friday afternoon, 14th Nisan Majority (Babylonian influenced) Calendar.
On page 221, Humphreys gives evidence that some Jews, according to the Jewish "Tosefta Pesahim", were bringing lambs to the Temple to be slaughtered before the official day of the 14th Nisan.  In the Moses tradition in Egypt, the lambs were slaughtered outside the front door of the place where the meal was going to be eaten.  It is this killing of the lamb themselves that the disciples might have been talking about when they spoke of "preparing the Passover" (Matthew 26:17, Mark 14:12, Luke 22:7-8), killing the lamb, not at the Temple, but at the front door of the place where they were going to eat.
So, according to Colin Humphreys, the Last Supper was a Passover meal, according to the Mosaic Calendar.
The two calendars revealed by the actions of the disciples
On Friday afternoon it is clear there was a bit of a rush for Joseph of Arimathaea to get our Lord buried and the stone rolled across the tomb before sunset, because for the Jewish authorities at sunset the Sabbath day started (John 19:31-42).
And we also see that Mary Magdelene was very keen to get back to the tomb to perform the rituals of the Jews for His body (Matthew 28:1, Mark 16:1, Luke 24:1, John 20:1) rising early, even just before dawn.  But the question is... Why didn't she go to the tomb immediately after sunset on Saturday night, when the Sabbath day officially ended, according to the Jewish Calendar of the Jewish authorities?  Why did she feel the need to wait until the dawn of Sunday morning?  The mystery is resolved once we appreciate there were two calendars in operation.  On Friday evening, Joseph of Arimathaea acted according to the requirements of the Babylonian-based calendar of the authorities: he either believed in this calendar himself or he obeyed it so as not to get into trouble with the authorities. But Mary Magdalene acted according to the requirements of the Mosaic Calendar in which the date and day changes at dawn: for the disciples the sabbath day did not end until the dawn on Sunday morning.  The women on Sunday morning left where they were staying, possibly at Bethany or Bethphage, before dawn, taking advantage of the allowance of a "Sabbath Day's journey" in order to reach the tomb as soon as possible.  By the time they had reached the tomb the sabbath day had ended.  The actions of the disciples is evidence of two calendars in operation.
Our Lord's obedience even to the details of Moses' Law
Some have suggested our Lord was not particularly fussy about following conventions or legalistic rules.  On the contrary, I put it to you that if our Lord Jesus had not celebrated Passover on the day that he did according to the Mosaic Biblical Calendar then he could not have been your Saviour or my Saviour or anybody's Saviour. He had to obey the Law of Moses in every detail, to be the spotless, sinless sacrifice.
When they celebrated the Last Supper it was our Lord Jesus and his disciples who were following the exact biblical pattern for the Passover meal given by inspiration to Moses and established through him as the pattern for all future generations.  If Jesus had followed the Babylonian Calendar used by the Temple authorities, it would have been contrary to the law of Moses, there would have been a stain, a blemish on his otherwise sinless life.  He could not have been our Saviour.
It follows from this that our Lord and his disciples, in the celebration of Passover, followed the Mosaic Calendar every year, and Joseph and Mary did too.  Our Saviour throughout his life obeyed the Law of Moses in every detail.
Finally, notice what is said in Matthew 28:1 :-

"In the end of the Sabbath, as it began to dawn toward the first day of the week, came Mary Magdalene and the other Mary to see the sepulchre."

I guess most readers of this have known for many years that the Jewish day and date changes at sunset. And I guess we have all read Matthew 28v1 without really giving it much thought.. I know I have for nearly forty years.  It tells us that Matthew was not using the Conventional Jewish Calendar based on the Babylonian Calendar.  The Babylonian-based calendar was not the only calendar in use at the time.  Matthew was using the Mosaic Calendar (when each day ended and the date changed at dawn rather than at sunset) rather than the Babylonian-based Conventional Calendar when the day changed at sunset.
Another verse to examine is Mark 14:12:

"And the first day of unleavened bread when they killed the Passover lamb..."

Here Mark cannot be using the Conventional Calendar in Mark 14:12, because in that calendar the lamb was certainly not killed on the first day of Unleavened Bread.  There was no way the lamb was killed and eaten the same day: in the Babylonian-based Conventional Calendar the Passover was killed on the afternoon of the 14th and the Passover meal was eaten after sunset which was the 15th.  With the Mosaic Calendar (when the day and date change at dawn) the Passover was killed in the afternoon and eaten after sunset on the same day, exactly as is being said in Mark 14:12.
The complexity of having two calendars running side by side is left out of the four gospel accounts.  Amongst other reasons, maybe limited space did not allow for it.  The synoptics were written before the destruction of the Temple.  When John wrote his gospel after the destruction of the Temple he wrote his account of the last week in harmony with the Conventional Jewish Calendar, maybe because the Mosaic Calendar was not so well attested in the literature, which was written by the elite.  It was the elite who would write the Talmud.
For more on this see "The Mystery of the Last Supper" by Colin Humphreys.  See also an article by Rabbi Israel Drazin "Biblical days started at daybreak not sunset".
Comment: **Comments have been [moved to chat](https://chat.stackexchange.com/rooms/144549/discussion-on-answer-by-andrew-shanks-was-the-last-supper-not-the-passover-meal); please do not continue the discussion here.** Before posting a comment below this one, please review the [purposes of comments](/help/privileges/comment). Comments that do not request clarification or suggest improvements usually belong as an [answer](/help/how-to-answer), on [meta], or in [chat]. Comments continuing discussion may be removed.
Answer: The following is a defence of the idea that the Last Supper was the "conventional" Passover meal held on the Thursday evening.  In this case the Thursday would have been 14th Nisan and the Thursday evening (and Friday daytime) would have been 15th Nisan.
I no longer believe this view is possible: the killer blow is that for AD 30 and AD 33 the Friday was not the 15th but rather the 14th Nisan.  Hendriksen believed the crucifixion was on Friday 15th Nisan AD 30.  But in that year Friday was on 14th Nisan:  Hendriksen (and others) who have thought the Friday was 15th Nisan were using incorrect astronomical data.  In AD 33 also Friday was on 14th Nisan, not 15th Nisan.  This completely ends the possibility that the Last Supper was a conventional Passover meal for these two years.
On the 14th the Passover lambs were sacrificed.  The Last Supper could not have been a "conventional" Passover meal on the Thursday evening because the lambs were
not yet sacrificed.
Having read "The Mystery of the Last Supper" by Colin Humphreys I now believe this resolves what has been a centuries long controversy.
Please do not mark this post up: it would be a meaningless vote.  I only leave this post in situ because it summarizes William Hendriksen's attempt, which I think gets as close as any other attempt to justifying the view that the Last Supper was a conventional Passover meal.
I will post another answer briefly explaining Colin Humphreys' position.
Thank you.
-=-=-=-=-=
Was the Last Supper not the Passover meal?
Consider a few verses:-
It was just before the Passover Festival. Jesus knew that the hour had come for him to leave this world and go to the Father. Having loved his own who were in the world, he loved them to the end. (John 13:1, NIV)
Then led they Jesus from Caiaphas unto the hall of judgment: and it was early; and they themselves went not into the judgment hall, lest they should be defiled; but that they might eat the passover. (John 18:28)
And it was the preparation of the Passover, and about the sixth hour: and he saith unto the Jews, Behold your King! (John 19:14, KJV)
So it was before the feast of the Passover that Jesus ate the Last Supper with his disciples ((John 13:1); he was brought out to the people by Pontius Pilate the sixth hour during the preparation of the Passover (John 19:14); and the religious leaders did not want to go into the hall of judgment (John 18:28) because they did not want to defile themselves because they wanted to eat the Passover.  What could be clearer?  But not so fast.
In the blue corner we have the traditional view that the Last Supper was the Passover or at least it was eaten immediately after the Passover meal (see the answer of user900).  For a defence of this position I shall rely on the Greek scholar and Bible Commentator, William Hendriksen, and his Commentary on John.
And in the red corner we have Colin Humphreys and his best selling book, "The Mystery of the Last Supper – Reconstructing the Final Days of Jesus".  I shall not comment on this position except to attack it. But, still, I give the name of the book for those who want to pursue the idea.  A favourable review of Humphrey's book is here:-
https://www.evangelical-times.org/book/the-mystery-of-the-last-supper/
Before looking at various texts and arguments let me lay out the generally accepted views of what is meant by the Passover meal. The Passover meal was kept in commemoration of the night the Israelites left slavery in Egypt as described in Exodus 12:1-17 and Leviticus 23:1-8.
The Passover lamb was killed on the evening of the 14th day (Ex 12:6).  The day following began the Feast of Unleavened Bread which lasted seven days (Lev 23:5-6). Strictly speaking there were two events, the Passover meal followed by the feast of Unleavened Bread lasting seven days.
But there are two problems with this:
Firstly, a comparison of Exodus 12:1-17 with Leviticus 23:1-8 can lead to some confusion: For instance, in Leviticus (23:6) the Feast of Unleavened Bread begins on the 15th, but in Exodus (12:18) it begins on the 14th.  In Exodus the Feast starts on the 14th and lasts until the 21st "for seven days", but actually that is eight days. And unleavened bread was eaten at the Passover meal (Ex 12:8).  And in Ezekiel we read "In the first month, in the fourteenth day of the month, ye shall have the Passover, a feast of seven days; unleavened bread shall be eaten. (Ezekiel 45:21) So the terms "week of unleavened bread" and "Passover" can sometimes be used interchangeably.
Secondly, neither the Greek New Testament nor the Hebrew Old Testament uses the term "afternoon" with the single possible exception, in some but not all translations, of Judges 19:8.  Even though Exodus 12:6 speaks of killing the lambs in the evening, the actual practice of the Jews in the New Testament era was to kill the lambs in the afternoon (Josephus, Jewish Wars, Book 6, chapter 9, note 3).  In this case evening was therefore interpreted as the time after the sun started going down from its zenith at midday.
It would seem that the festival was eight days as long as you include the slaughtering of the lambs during the afternoon of the first day but that the eating of the festival was seven days remembering that the Passover meal was to be eaten after sunset when the first day had ended and a new day had begun.
Rather than try to understand this perfectly it is probably better to know what the Jews actually did in New Testament times.
According to Josephus, the lambs for Passover were sacrificed on the 14th Nisan: in his book "Antiquities" he relates "when the fourteenth day was come, and all were ready to depart they offered the sacrifice, and purified their houses with the blood" (Josephus, Antiquities, chapter 14, Paragraph 6).
And he also tells us the lambs were sacrificed from "the ninth hour till the eleventh", that is in the afternoon (Josephus, Jewish Wars, Book 6, chapter 9, paragraph 3).
And Josephus speaks in one place of the Feast of Unleavened Bread lasting eight days, when strictly it was only seven days (Antiquities, chapter 15, paragraph 1): clearly he here includes the Passover (or is it the day of the afternoon sacrifice?) as part of the Feast of Unleavened Bread.
In Luke 22:1 just as in Ezekiel 45:21 the whole week is called Passover: "Now the feast of unleavened bread drew near which is called Passover" (Luke 22:1).  In Acts 12:3,4 "Passover" ("Easter", KJV) clearly means the whole week. And sometimes the whole week including the Passover is called the Feast of Unleavened Bread (Matt 26:17, Mk 14:1, Mk 14:12, Luke 22:7).
With this in mind let us examine the three verses mentioned at the start:-
On John 13:1
There is a huge difference between the NIV translation and say the ESV:
It was just before the Passover Festival. Jesus knew that the hour had come for him to leave this world and go to the Father. Having loved his own who were in the world, he loved them to the end. (John 13:1, NIV)
Now before the Feast of the Passover, when Jesus knew that his hour had come to depart out of this world to the Father, having loved his own who were in the world, he loved them to the end. (John 13:1, ESV)
William Hendriksen argues for a translation very similar to the ESV, but perhaps more clear:
"Now Jesus, knowing (already) before the feast of the Passover that his hour to depart out of this world (and to go) to the Father had arrived, having loved his own on the world, loved them to the uttermost." (John 13:1, Hendriksen)
In the ESV and in Hendriksen's translation "before the feast of the Passover" indicates when Jesus knew.  It does not indicate when the events described actually happened.
On John 18:28
Then they led Jesus from Caiaphas unto the hall of judgment: and it was early; and they themselves went not into the judgment hall, lest they should be defiled; but that they might eat the passover. (John 18:28)
This is more difficult: but these religious leaders were hypocrites, and I think we can rely on them to ignore the spirit of the law, just so long as they felt they could keep the letter of the law.  And who shall decide the exact interpretation of the law except they themselves?  And when the law says that none of the lamb shall be left until the morning, who decides when the morning starts?  It is clear to see that they wanted a very quick decision from Pilate.  With this in mind..
The Passover lamb had to be eaten during the night, it could not be left until morning.   And it was already morning when they first delivered Jesus to Pontius Pilate (Mark 15:1), so the dawn had already started when they chose not to enter the judgment hall (John 18:26).  But after this Pilate sent Jesus to Herod, and after Jesus had been sent back to Pilate by Herod it was still (only) about the sixth hour, that is about 5am or somewhere between 5am and 6am.  So at the time the Jews chose not to enter the judgment hall, even though the dawn had started, they felt there was still time to eat the Passover before the start of sunrise, which I suppose they themselves had decided was the time after which the Passover could not be eaten.
On John 19:14
And it was the preparation of the Passover, and about the sixth hour: and he says unto the Jews, Behold your King!
In John's Gospel the term "unleavened bread" is never used, but only "Passover".  When John speaks of the whole week of festival he uses "Passover", eg John 2:23.
Where Scripture speaks of the "preparation of the Passover" (John 19:14) it means preparation day of the Passover week, meaning the Friday of Passover week. "Preparation Day" was the day of preparation for the Sabbath day (John 19:31).  Even today, in the Greek language the literal meaning of the word for "Friday", Παρασκευή -Paraskevi, means "preparation".
This is confirmed in Mark's Gospel:
And now when the even was come, because it was the preparation, that is, the day before the Sabbath.. (Mark 15:42).
Summary
There is no contradiction between John's Gospel and the other three.  The Passover lambs were slaughtered on the afternoon of Thursday the Nisan 14th, the Last Supper which was the Passover meal was eaten after sundown on Thursday the 15th Nisan, our Lord was crucified on Friday the 15th Nisan and rose again the third day.  And to understand what "third day" means we can read what our Lord said:

And he said to them, "Go and tell that fox, 'Behold, I cast out demons and perform cures today and tomorrow, and the third day I finish my course. (Luke 13:32)
Comment: @Anne - Thank you & v well spotted!  Yes I have changed my mind and now follow Colin Humphreys.  William Hendriksen was wrong, clearly because he followed astronomical data which said Friday was the 15th Nisan: this was impossible for AD 33 (which I am sure was the correct year (and also AD 30 for those who prefer that year).  Friday 15th is only true for AD 34, but that year most reject as too late.  I have a list of posts which I need to change & this one is top of the list.  I think rather than change it I will say it is no longer my view & write the Humphreys view.  I will do asap, thanks!
Comment: Given your new answer 5 days ago to an 9.5-yr-old Q on the date of the crucifixion, have you changed your mind about Colin Humphrey's book, 'The Mystery of the Last Supper'? Have you been won over by Humphrey's arguments in the space of less than 2 months? If so, might it be best to change your comments about Humphreys in this answer? Or have I misunderstood?
Comment: I dissagree with the A.D 33 date. There is a massive problem with this date because it conflicts with the 70 week prophecy of Daniel 9:27. "He will confirm a covenant with many for one 'seven.' In the middle of the 'seven' he will put an end to sacrifice and offering." If Jesus ministry started in AD 27 then he had to die no more than 3.5 years later...that is about AD 31 and no later than this...not only for his birth date but also the average age of a new ordained priest (which i believe was about 30 years of age). Jesus earthly ministry should agree with those traditions of the Israelites.
Comment: I know some make the claim that Daniel 9:27 is Antiochus, that is an easily bebuncted theory...i would suggest one starts by reading Daniel 9:24 "From the issuance of the decree to restore and rebuild Jerusalem, until the Messiah,g the Prince, there will be seven weeks and sixty-two weeks" 26Then after the sixty-two weeksh the Messiah will be cut off and will have nothing(69 weeks)
Comment: I'm only good at spotting problems with words, Andrew; I'm a numerically dyslexic numptie with figures (111 gives me no difficulty but 106 could end up as 601 or 610 or 160 in my brain!) I cannot begin to understand calculations needed for Qs like this. Until the exact date of Jesus' birth is set in stone, I'm going to leave all such matters alone (and reflect on the fact that such a date is deliberately not stated in scripture.) Keep up the good work.
Comment: @Adam - I think you must have added comments to completely the wrong post.. this answer is nothing to do with 33 AD.  Also I suspect it was you who marked this post down (?)  That's fine, it is now meaningless for this post to be have anything other than zero points.   If I knew which post you meant to write this for then I could perhaps respond.
Comment: @Andrew Shanks, you are incorrect at the beginning of your answer where you say the 14th of Nisan in AD 30 was a Friday.  It was not.  It was a Wednesday and supports a Wednesday crucifixion view, with Jesus in the tomb 3 full days and nights and rising at sunset sunday morning when the day began at sunset.  The confusion arises in confusing the weekly saturday sabbath with the Passover Sabbath that was on Thursday in AD 30.  This link shows the day of the week for AD 30.  https://peacecrusader.wordpress.com/2009/07/19/was-jesus-crucified-sometime-in-a-d-30/
Comment: @DDover - The website you are relying on is entirely wrong.  Use either the standard chronological work for the last 70 years "Babylonian Chronology 626 BC  to AD 75" by Richard A. Parker & Waldo Dubberstein, or look at the more recent astronomical calc.s at website "Jewish Calendar" by astronomer Rita Gautschy, for sighting date and time of the new crescent moon (Jewish conventional lunar day 1) in March AD 30.   These two sources agree 100%.  In P&D 1st Nisan AD 30 was 25th March (the evening before was also 1st Nisan, 24th Mar).  Gautschy's file agrees 1st Nisan evening was 24th Mar,
Comment: @DDover - was 24th Mar.  These Julian dates produce the Julian date 7th April (daytime) for 14th Nisan.  7th April (Julian) which is 5th April (Gregorian) can then be entered into onlineconversion.com/julian_date.htm to find the day of week, (Friday).
Comment: @Andrew Shanks, as I try to research this there seems to be two competing views with those who insist 14 Nisan AD 30 was Wednesday and others that its Friday.  I'm left with taking your word for it, and I can't just do that.  It seems most of those who claim it was April 7th are of a mind the Bible says the crucifixion was on a Friday, and I have to wonder if they're biased.  As far as Jesus being in the grave for 3 days and 3 nights, you can't find even 3 partial nights from Friday to Sunday morning.   http://www.studiesintheword.org/chart_22-36AD.htm
Comment: @DDover - none of my sources are biased because none of them are Christian.. they have little interest in the date of the crucifixion.. Rita Gautschy is an astronomer, Parker was a famous archaeologist for Middle East and Egypt, Dubberstein was also an ME archaeologist.  Their book was built on the work of many archaeologists, and many thousands of hours of labour.  Matt 12:40 is an idiomatic expression meaning portions of three 24 hour periods, same as Esther 4:16 which ended on the _3rd_ day (Es 5:1). Jesus rose on Sunday, the 3rd day (see Luke 13:32, Levit 7:15-17). Happy researching!
Answer: Was the Last Supper not the Passover meal?

John 18:28 - they did not enter into the Praetorium so that they could eat the Passover ...

Which means: NO, the Passover feast had not been eaten yet.
It is possible to resolve all contradictions by removing the traditional beliefs, and considering the fact that weeks can have double Sabbaths involving high holy days.
The Consummate Refutation of Christianity—if the Last Supper was a Passover Feast
On it's face, the question presupposes that the many thousands of Passover Lambs had already been sacrificed.
If Jesus' death wasn't the fulfilment of the Passover Sacrifice, then consequently—all New Testament theologies and apologetic arguments are irretrievably lost.
In other words, The traditional doctrine that the Last Supper was a Passover feast is antithetical to Jesus being the fulfilment of the Passover laws and promises.
There are simply way too many contradictions and direct textual statements that contradict this Tradition—and yes, that theology is only a Tradition.
If the Last Supper was actually a Passover feast, then Jesus and his disciples broke many Passover laws. See the Hermeneutics post: According to the Gospels, Was the Last Supper Actually a Passover Feast?.
Comment: Pretty sure it's an abuse of the Christianity stack to come here and claim *Christianity is a false religion.* Also, as to John 18:28, there are plausible solutions to the percieved issue about the Passover; see [Haydock](https://www.studylight.org/commentaries/eng/hcc/john-18.html) for v.18 for example. Finally, if Jesus was fulfilling the Passover as a type, He need not obey Rabbinic minutia that accumulated over time, nnor merely recapitulated the Feast exactly, word for word, merely substuting Himself for the Lamb. That's not what 'the New Passover' means.
Answer: Introduction
The Last Supper was not a Passover seder. The Passover seder occurred immediately before the Last Supper during the same evening. This is only evident when we closely examine the Gospel of Luke.
Analysis
In Luke 22:7, it is written,

Then came the day of Unleavened Bread during which the Passover lamb must be killed.
Ἦλθεν δὲ ἡ ἡμέρα τῶν ἀζύμων ἐν ᾗ ἔδει θύεσθαι τὸ πάσχα TR, 1550

This "day of Unleavened Bread" refers to Nisan 14, as the Jews reckoned even this day, although properly "the Passover" (Exo. 12:6), as the first day of the Feast of Unleavened Bread. In fact, they often called the entire "Feast of Unleavened Bread" by the name "Passover."1
Thus, on Nisan 14, the day on which the Passover lamb was to be slaughtered, the Lord Jesus Christ commands the apostles Peter and John to "go prepare the Passover so we may eat" (Luke 22:8). They then went to Jerusalem and found the man Jesus instructed them about (Luke 22:10-12), "and they prepared the Passover" (Luke 22:13).
In Luke 22:14, it is written,

And when the hour came, he reclined, and the twelve apostles [reclined] with him.
Καὶ ὅτε ἐγένετο ἡ ὥρα ἀνέπεσεν καὶ οἱ δώδεκα ἀπόστολοι σὺν αὐτῷ

The Lord Jesus Christ and the twelve apostles reclined and began to eat the Passover seder.2 He says to the twelve, "I have earnestly desired to eat this Passover with you before my suffering" (Luke 22:15). Then he says to the twelve, "I will not eat of it anymore until it be fulfilled in the kingdom of God." But, that Jesus ate then and there, it is certain (cp. Matt. 26:21; Mark 14:18).
The Lord Jesus Christ then receives a cup, gives thanks to the Father, and says to the twelve, "Take this [cup] and divide it among yourselves" ([Luke 22:17]]10). Based on these words, it is arguable that the Lord Jesus Christ himself drank from the cup; however, it seems likely that he did.3
Now, at this point, the Lord Jesus Christ had been eating the Passover seder with the twelve, and he drank a cup of wine and distributed to his apostles. After this, note the following:
In Luke 22:19, it is written,

And when he took bread, giving thanks, He broke [it] and gave [it] to them, saying, "This is my body which is given for you. Do this in my memory."
καὶ λαβὼν ἄρτον εὐχαριστήσας ἔκλασεν καὶ ἔδωκεν αὐτοῖς λέγων, Τοῦτό ἐστιν τὸ σῶμά μου τὸ ὑπὲρ ὑμῶν διδόμενον τοῦτο ποιεῖτε εἰς τὴν ἐμὴν ἀνάμνησιν

Luke 22:19 is the verse which demonstrates the commencement of the Last Supper.
In Luke 22:20, it is written,

Likewise, also the cup after eating the meal, saying, "This is the cup of the New Covenant, with my blood which is shed for you.
ὡσαύτως καὶ τὸ ποτήριον μετὰ τὸ δειπνῆσαι λέγων, Τοῦτο τὸ ποτήριον ἡ καινὴ διαθήκη ἐν τῷ αἵματί μου τὸ ὑπὲρ ὑμῶν ἐκχυνόμενον

Notice that the Lord Jesus Christ had already distributed a cup to the twelve (Luke 22:17) during a previous meal, and after eating that meal (μετὰ τὸ δειπνῆσαι), he takes bread (Luke 22:19) and then another cup (Luke 22:20)! This is the evidence that two meals are involved. Two cups; two meals. The first meal was the Passover seder; the second meal is the Last Supper. They are not the same meal. The Passover seder was not the Last Supper. The first cup was actually the last of the four cups of the Passover seder, thus completing the Passover seder. The second cup was the cup of the Last Supper.
John Gill on Luke 22:19,

Here begins the account of the Lord's supper after the passover was eaten.

Count the cups...it's only in Luke's Gospel, but it's there.

Footnotes
1 cp. Luke 22:1; Josephus, Jewish Antiquities, 2.15.1.
2 It was custom to recline while eating the Passover seder. See Jerusalem Talmud, Tractate Pesachim, Chapter 10, Folio 68b, Halakha 1: ולפי שדרך עבדים להיות אוכלין מעומד וכאן להיות אוכלין מסובין להודיע שיצאו מעבדות לחירות, that is, "Because it is the custom of slaves to eat standing, here [it is the custom] to eat reclining to proclaim that they have gone out from slavery to freedom."
3 See Meyer's commentary on Luke 22:17.
4 The phrase μετὰ τὸ δειπνῆσαι is the preposition μετὰ, meaning "after," followed by the substantive infinitive τὸ δειπνῆσαι, meaning "dining" or "eating (a meal)." It simply refers to eating a meal. Although the KJV translates it simply as "supper," as though it was a noun, it should not be assumed that this "supper" is the "Last Supper," as many may erroneously assume. BDAG defines the verb as, "to eat a meal (without ref. to time of day or type of food), eat, dine."
Comment: You say "Two cups; two meals", but the Passover Seder has 4 cups imbibed at different times in the Seder.  http://en.wikipedia.org/wiki/Passover_Seder#The_Four_Cups
Comment: @a_hardin: I am well aware...but most would agree that the cup Jesus drinks is the last of the four...Nevertheless, I might be wrong about him drinking two cups (for two different meals) after all. I will delete this if I come to that conclusion.
Comment: In Luke 22:18 Jesus days he will not drink the fruit of the vine until the Kingdom of God comes, and then in verse he drinks wine. Are we to suppose that he meant he wouldn't drink wine at any subsequent Passovers, just at that one?
Comment: Where is your evidence that the 14th was the first day of unleavened bread?  It does not agree with Lev 23:6-7.  The first day is a special sabbath.  How could they have be doing all the work of preparing the passover lamb on a special sabbath day?  The 15th was the first day of unleavened bread.
Comment: @user900 I disagree that the cup of Luke 22:17 must be the last of the four, and you don't give any evidence. And if that's not the case you have no evidence that 2 meals were involved, which means that your entire case falls apart.
Comment: Note specifically that in the [Seder order](https://en.wikipedia.org/wiki/Passover_Seder#Order_of_the_Seder) the fourth cup is drunk after the [Birkat Hamazon](https://en.wikipedia.org/wiki/Birkat_Hamazon), which is the prayer used at the end of a meal. Thus the cup of Luke 22:20  can be the fourth cup of the Seder and still  be "after the meal".
Answer: The entire week of Passover ("pascha") is a feast of unleavened bread, and as the following quote notes, the 14th of Nisan in popular usage is a holiday that was combined with the passover starting on the 15th, and so Jesus eating the passover on the 14th of Nisan was really all part to an 8 day passover period.  The next day, the 15th of Nisan, is the Passover Sabbath, and it is treated like a Sabbath in which no work can be done regardless of which day of the week the 15th falls on (see Lev. 23).

. . . pascha can denote the meal that was eaten on the 14th of Nisan, the first month of the Hebrew calendar (Mt. 26:18-19; Lk. 22:8, 13; Heb. 11:28).

But it is also the case that the term pascha can refer to the entire eight-day period which included the feast of unleavened bread — thus from the 14th of Nisan to the 21st. Note this passage:

In the first month, on the fourteenth day of the month, you shall observe the Passover, a feast of seven days; unleavened bread shall be eaten" (Ezek: 45:21; cf. Lk. 22:1, 7; Acts 12:3-4).

F.W. Danker7 notes: "Popular usage merged the two festivals and treated them as a unity, as they were for all practical purposes."

There were several "feasts" during this period (see 2 Chron. 30:22); the one mentioned in John 18:28 may have been on the day following the main Passover supper. It was called the Chagigah (sacrificial meal). This view is defended by many respectable scholars, e.g., Lenski and Edersheim. Edward Robinson has a clear and detailed explanation of this position that is worthy of serious consideration, and, in this writer's judgment, this argument carries the greatest weight of evidence8.

https://www.christiancourier.com/articles/390-did-jesus-eat-the-passover-supper
Hebrew days run from sunset to sunset, and thus all on the same day Jesus at the Passover meal, was arrested that evening, had his trial that morning, was crucified and died on the cross during the daylight hours. This all occurred on the same day, the 14th of Nisan.  There is no problem with Jesus eating the Passover on the 14th since popular usage combined the holiday of the 14th as part of the entire Passover week long holiday.


How JBL app recognises the speaker name, colour etc, when connect via Bluetooth from my iPhone?

Question: Few days back I bought Jbl Charge 3. When I connect the speaker with Jbl connect app on my iPhone I found it was giving some additional information apart from receiving audio file. It recognises that it's a jbl charge 3 and even knows that its is of red colour( I tried with black speaker it did same, recognise that it is black in colour). I am not from IT background. Can any one tell me how it works?
Thanks
Answer: The JBL Charge 3 uses and transmits metadata from the speaker to your phone using different Bluetooth protocols listed below. HFP is the most likely of the candidates that transmit the information about your JBL Charge III. See below for more info.

A2DP V1.3 - Advanced Audio Distribution Profile. This is the Bluetooth Stereo profile which defines how high quality stereo audio can be streamed from one device to another over a Bluetooth connection.
AVRCP V1.5 - is typically used with A2DP devices for next/previous track selection and pause/play functions.
HFP V1.6 - is a hands-free protocol that transmits battery, allows phone calls to be passed through, and other functions of the phone that may be distracting.
HSP V1.2 - This is the most commonly used profile, providing support for the popular Bluetooth headsets to be used with mobile phones. It relies on SCO for audio encoded in 64 kbit/s CVSD or PCM and a subset of AT commands from GSM 07.07 for minimal controls including the ability to ring, answer a call, hang up and adjust the volume.

Source(s)
https://en.wikipedia.org/wiki/List_of_Bluetooth_profiles
https://www.jbl.com/bluetooth-speakers/JBL+CHARGE+III.html


GIMP Stroke selection is disabled?

Question: I am working to make a border for a GIF. May I ask please how to enable the stroke selection for a new layer in GIMP?
Answer: As far as I can tell from your screen shot, you haven't made a selection. Stroke selection will be greyed out if you don't have a selection.
The yellowish dotted line around your image is not a selection, it's only the layer boundary.
A selection looks different from the layer boundary, it has a "marching ants" animated effect, and is not yellowish.
You can switch off the layer boundary if it's confusing you. Click View in the main menu, and deselect the Show Layer Boundary option.
If you want to select the entire image hit Ctrl+A(Select all). Now you can stroke it using Stroke Selection.
Comment: thank you for your help. It is GIF file May I ask please if it is also true for GIF file?  I would like to add a border in a GIF file.
Comment: If you want to add a border to an animated GIF, then you'd have to add it on every frame of the animation, which could be a bit tedious. I'm unfamiliar with the GIMP FAnim Timeline plugin you are using, but if it's anything like Photoshop's timeline, then you could just add the border to a new transparent layer, and use the timeline plugin to add it to each frame (this is just a guess, so don't hold me to it).
Answer: you can take you selection and left click it in the layer tab, select 'alpha to selection, then in the path tool, add a new path layer, and at the bottom use the 'selection to path' icon.  Then stroke path.

GIMP Stroke selection is disabled?


EIP 1559 - Set both priority fee and max fee to the same value

Question: :)
Can someone explain to me how this is possible?
I mean from EIP1559 documentation is it said that if the max_priority_fee + base_fee > max_fee then the max_priority_fee is reduced. (https://www.blocknative.com/blog/eip-1559-fees)
In this case:
12.869999013 + 45.87682593 = 45.87682593 (indeed lol) so the max_priority_fee should be reduced to 45.87682593 - 12.869999013 = 33.006826917
So it should be:
base_fee = 12.869999013 Gwei
max_fee = 45.87682593 Gwei
max_priority_fee = 33.006826917 Gwei

But i really don't understand how in this case the guy manage to set the max_fee and max_priority_fee to the same value.
The hash of the tx if you need more info -> 0xed0f9da824070b042ddadaaaa408f5c53aeabcc5222410bafd2d91c4645a69c7
Btw to let you know, when i create my own tx in rust and set the max fee equal to the priority fee, the priority fee is reduced to match max fee - base fee when i simulate the transaction.
What i want to reproduce is to have the same value in those fields so i will know exactly what i will spend, i know this may not seem to be necessary but this is mandatory for me and my app !
Thank you for your clarification and your help and have a great day everyone.
Answer: to answer your question

so i will know exactly what i will spend

you will spend maximum of maxFeePerGas or baseFeePerGas + maxPriorityFeePerGas if the sum is lower, than maxFeePerGas


gdb - searching for pointers to a given memory region

Question: Let's suppose there is a memory region that is m'mapped in memory, we need to find its address (which randomly changes, because of ASLR) by following a pointer path, basically, I'm trying to find a possibly multilevel pointer that leads to any address in that memory region, and that starts from an address in a memory region I choose, is that possible to do with gdb? I've checked out the popular gdb extensions (peda, pwndbg), but didn't find such a feature, if there is no existing implementation, any tips on how to optimize the search? Kind of like the Pointer Scanner of Cheat Engine, pointers can also have offsets (for example : main_module+3170 -> 0x7fff42dc7220 ; 0x7fff42dc7220+10 -> 0x7ff464213460 ; 0x7ff464213460 -> address wanted).
This would be useful for example in a context where we have a write-what-where condition (we can write or read anywhere in memory), and we need to defeat ASLR to find interesting memory regions (for example, JIT buffers in browsers).
Answer: I know that this post is now more than 4 years old, but: We created a gdb extension that can do just that. It's available here: https://github.com/ChaChaNop-Slide/ptrfind


Tricks to make a small image to take up a large space on a webpage

Question: I need to create profile webpages for many people (100++ pages) and most of their profile photos (about 400x400) are small in dimension. But I have a large image space (1280x720) that I need to fill in on each page. What is the best way to fill in the empty space? Do I superimpose the small profile photo on a larger backdrop? If so, do you know any examples? Or do you know any better alternatives?
Comment: I'm afraid a sample image may be necessary. It's difficult to provide any suggestions without actually seeing the issue since "space" - large or small - is relative.
Comment: @Scott Profile photos are like 400x400 and the large space is like 1280x720
Comment: Were you hired as a 'page filler' or as a designer?
Answer: I'd again ask for an image to show the overall layout.
One can not make adequate special suggestions without seeing a representation of all the elements in play. It's possible that nothing needs to be done. A great deal of space can promote a more professional appearance.
Based purely on measurements provided, I see no reason to "fill" a larger area with something to make a 400x400 headshot "fit better". I think it fits fine.
Of course, layout matters. Without more information, it's difficult to be more definitive.
Answer: If you really cannot modify the layout (i.e. reduce the space), I'd use a light, grayscale, low-contrast, low-information, blurred background image. Maybe one representing the organization somehow, maybe just something that fits the overall design.


Which Italian provinces get ceded to the Pope on creation of HRE?

Question: I'm trying to create HRE and the Pope is asking for several provinces to be ceded in exchange. How is it determined which counties must be handed over? In my case he wants Ferrara, Ravenna, Spoleto and Urbino. Ferrara and Ravenna are both a part of my demesne and as a result I'm reluctant to hand them over.
Comment: This is about a video game, don't mind if it's a little bit different from history. I want to know how the game computes the provinces to hand over so that I can keep my demesne at least.
Comment: Are you asking for what happened in real history, or a strategic hint, or something else?
Answer: Pope always asks for Rome, Ravenna, Ferrara, Urbino, and Spoleto, but only if the current holder has other titles owned.
See form_the_hre_early in realm_decisions.txt


HTML mobile app with offline storage only

Question: I need to create a mobile app based on HTML5 that would run on iOS devices (iPhone, iPad) and Android phones and tablets.
The app is about storing grocery items.  I will have categories and items along with images for items.  All this data will be generated by the user of the app.
The app will not require any network connectivity and just need to store the data offline.
I am thinking I can use the following technologies for this app and would appreciate some guidance:
1) PhoneGap - I think I will be able to use the Storage API provided.
Will this allow me to create a SQLite database on the device and the ability to perform CRUD operations on the data?
Also, is there a space limit?  I was looking at LocalStorage, WebSQL.... really confused about storage.
2) KendoUI Controls for Mobile - use this to create the layout.  The question here is that can KendoUI be used with PhoneGap for offline storage.  All examples of KendoUI seem to work with data from network services.... not much guidance around offline storage.
Thanks.
Answer: All Kendo widgets can operate with remote and local data. To read and write data at LocalStorage or WebSQL data base you should create a custom transport. Check the following examples:

KendoUI and WebSQL
KendoUI and LocalStorage


Reliable transport protocol on top of UDP

Question: UDP has one good feature - it is connectionless. But it has many bad features - packets can be lost, arrive multiple times, there is no packet sequence - packet 2 can arrive faster than 1. How to keep good and remove bad?. Is there any good implementations that provide reliable transport protocol on top of udp so that we are still conectionless but without mentioned problems. One example of what can be done with it is mosh.
Answer: What you describe as bad isn't really bad depending on the context.
For example UDP is used a lot in realtime streaming, delivery confirmation and resending is useless in this context.
That being said there are e few implementations that you might want to look at:
ENet (http://enet.bespin.org/)
RUDP (https://en.wikipedia.org/wiki/Reliable_User_Datagram_Protocol)
UDT (https://en.wikipedia.org/wiki/UDP-based_Data_Transfer_Protocol)
I work in embedded context:
CoAP (https://en.wikipedia.org/wiki/Constrained_Application_Protocol) also implements a lot of these features, so its worth a look.
What is your reason for not choosing TCP?
Comment: sorry I don't know enough about other languages to give a good answer. We use C and C++ for performance on embedded devices. Making it stable is just A LOT of testing. Unit testing, integration testing etc.. But i cant really say if there are better options and/or pros/cons


Is it a good idea to add a booking flow inside of a bottom sheet modal

Question: I decided to include a booking flow inside of a bottom sheet modal so that the user doesn't need to leave the practitioner's profile to book an appointment with them. Is this okay?
Comment: Hard to say without a broader perspective of the user process. Does the [modal bottom sheet](https://pub.dev/packages/modal_bottom_sheet) activation control interfere with the practitioner's profile page? Does the modal bottom sheet provide everything necessary for the user to make a booking? If no and yes, then why not?
Comment: If this step is a side-step, then I would consider using a bottom sheet modal, like sharing the info of the ticket with your partner/friends/family. If this step is in the process of completing it, then I would not suggest using the modal.
Answer: "Why do the users need to stay on the practitioner's profile when booking an appointment?"
I think answering the above question would guide you in choosing the design. What information should be in front of users' eyes when they are booking an appointment?
Modal bottom sheets cover a good portion of the bottom part of the main content, so you obviously can't have the practitioner's available times there, for example.


Should the SQA Team participate in delivering the product to the customer?

Question: At my company, we don't have enough resources to hire a product owner to do this job (deliver the product to the client). Now, the PM is the responsible for this. But, if the SQA team (or one of its members) know the customer needs inside the company and gather its software requeriments, we suppose they have to participate in the delivery too, so we think is something that can be achieved through the SQA Team. Is a good policy? How must to be the relation between the SQA team and the customer?
Comment: @JoeStrazzere, it constitutes the process of (1) do a release of the project, (2) have a meeting with the customer, (3) install the software in its production enviroment (or deliver the app for mobile or desktop applications).
Comment: @JoeStrazzere - could you expand that comment into an answer? I think it would make a good answer to this question.
Answer: I believe QA should be involved in all aspects of the software design and development process.
I believe that if QA is involved early enough in the process, bugs can be avoided rather than merely detected and fixed. In the best situations, I've had my teams participate in all Requirements and Specs reviews. They were trained experts at spotting inconsistencies and omissions - highlighting these and having them fixed during reviews meant that the product owners, product managers and developers were more in synch. This resulted in fewer bugs in the eventual code.
When configurations and migrations occurred during the installation process, I believe that QA can play a significant part in checking the results of the installation - ensuring that they meet expectations.
I believe that it may not be necessary for QA to specifically meet customers, although I have seen it be a useful adjunct to more effective testing. In one early-stage startup, we got to meet the first Beta customer and see how she actually performer her job. That allowed us to imagine how her job could be simplified/enhanced as we developer the software her company would eventually use. We even had a way to look at features and issues that we called "The Barbara Test"
I don't think QA can be a de-facto Product Owner. Nor do I think QA can take the place of a real Product Manager. I don't think QA should own responsibility for gathering product requirements. But I do think that QA can aid by participating in much of the product development cycle.
Answer: Software quality has a broad scope. Just like Joe says I believe QA should be involved in all aspects of software development. Each person/company just has to find out how much effort and which is appropriate for their situation.

Is a good policy?

Probably not. As an SQA person that has a lot of dual roles in the past I have learned that a lack of focus hurst both roles. Also it hard to decide where your priorities should lay. In your case what is more important delivery or preventing defects. This switches all the time. Someone with a dual-role needs to continuously look critical at their workload and evaluate if they are taking the right actions.
Can it be done, surely. If you're at a small company it is common that people have a lot of dual-roles. Making stuff happen is important skill as well.

How must to be the relation between the SQA team and the customer?

However the team sees it fit. There is not a single best practise you should follow. Experiment, retrospect and adapt. Find a cycle where you keep questioning if this situation is still optimal and improve in small steps.
Comment: the "dual roles" thing is a very nice point of view. Unfortunately, in a small company like ours is difficult to do not have multiple roles sometimes. However, is a important thing to consider, so we will. Thank you so much for your answer.
Answer: I'll take a risk and disagree with Joe ). As it seems to me in a well-built process QA should not participate in release delivery (as per your definition of this term) however this might depend on what your release looks like and what your QA looks like.
I do not think a usual QA-man should be an expert in customer relations or release implementation. Participating in activities which are non-relevant to their skills might give them an extra headache and decrease productivity in their skill-relevant things.
I vote for just a logging of release delivery phase what can further be analyzed by a project manager who can then communicate some QA-relevant moments to the team.


Is there a way to set the next post ID to something very high?

Question: I have two WooCommerce shops for the same client, one for the US and one for CAD.  We want to make sure there is no collision with respect to the order numbers on these two shops, so I want to set the next post ID on the CAD site to 900001 and then go from there (we don't get a lot of traffic).  Is there a way to do this without using a sequential order number plugin?  It seems I should just be able to create a post with this ID using the API and then the database will autoincrement from there?
Answer: Yes, you can increase the next post ID.
The next value is controlled by the AUTO_INCREMENT setting of the post table in your database.
If you use phpMyAdmin, you can do this by opening up the post table (my prefix is wp1, therefore my table here is wp1_posts), then select the "Operations" tab and then increase the value in the AUTO_INCREMENT field.

The alternative is doing this with an SQL query like:
ALTER TABLE `wp1_posts` AUTO_INCREMENT=900001

When I tried this out I ran into a small problem.
I got the error message:

#1067 - Invalid default value for 'post_date' posts

I was able to solve it by first running the following query and then the query to increase the AUTO_INCREMENT value:
ALTER TABLE `wp1_posts`
  CHANGE `post_date` `post_date`  DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  CHANGE `post_date_gmt` `post_date_gmt`  DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  CHANGE `post_modified` `post_modified`  DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  CHANGE `post_modified_gmt` `post_modified_gmt`  DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP

That query is also necessary in case you use the "Operation" site in phpMyAdmin.
So first run it, then change the AUTO_INCREMENT setting.


How does Jashobeam become Iesebaal, or Jeshebeab become Isbaal?

Question: I was wondering if you could help me out with this. The names of Jashobeam, one of King David's warriors (I Chon. 11:11), and Jeshebeab, one of the twenty-four families of Kohanim (I Chron. 24:13), are translated in the Septuagint as Iesebaal and Isbaal respectively. I was wondering if you could help me find out more about this translation and other renderings of those names. I see that the Vulgate and various fragments of the DSS mirror the Masoretic version (as do the Vulgate and Peshitta) and do not have names theophorically recalling Baal. Are there any other translations/versions of the Bible which follow the LXX on this? Why would the LXX make such a change to the names of these people?
Answer: It is not so much that the names have been altered in the Septuagint (LXX) but that the LXX probably preserves the original names, which have been altered for theological reasons in the Masoretic Text (MT). Jeffrey H. Tigay says ('Israelite Religion: the Onomastic and Epigraphic Evidence', page 157) "For centuries after their occupation of Canaan the Israelite tribes remained polythistic, differing little from their neighbors except in the identity of their own chief or national deity."
Then on pages 160-1:

The Israelite theophoric names preserved in the Masoretic Text are overwhelmingly Yahwistic ...[A] certain percentage of pagan PNs has been altered in the MT to a point where they are no longer recognizable to us, and the MT cannot be automatically assumed to present us with a reliable impression of the extent of the use of pagan theophoric names in ancient Israel.

Tigay goes on to say that recent archaeological discoveries indicate "that ba'al names remained in use longer, and may have been more popular than the biblical evidence suggests."
Tigay says (ibid, page 161) that Jeshebeab and Jashobeam are read in the MT as Isbaal and Iesebaal respectively. Tigay believes the MT names to be later substitutions.
Even within the Masoretic text, we find instances where a pagan theophoric name and a neutral pseudonym are sometimes used for the same individual. Gideon's birth name is clearly Jerubbaal (May Baal Contend). Not only is the name Gideon a substitution, but elsewhere in the MT his name is also given as Jerubbeshet.
Comment: So you are saying that the LXX preserves a pre-censored version of a tradition older than the MT? Does this mean that only the names Jeshebeab and Jashobeam were censored by the MT because we don't find other instances of LXX translating a name differently than the MT. If this is true, then it would suggest that Baalic names weren't as possible as you are trying to make them out to be, because there are only a handful in the entire Bible. And if you want to say there were really more, then why does the LXX single out Jeshebeab and Jashobeam and not those others?
Comment: In some cases such as these, yes, the LXX preserves an earlier version of their names. In many other cases, the MT is considered more reliable thant the LXX. By no means were these the only names altered, but I focussed on the ones you asked about.  I added the example of Gibeon, where even among Hebrew authors, as comes down to us in the MT, to show how this 'censorship' worked. Please don't think I'm  "trying to make them out to be" something improper - I'm reporting what a representative scholar says. .../
Comment: .../ I found this item on the web because I already knew the answer (in general) and wanted an online reference that you could look up and which specifically dealt with Jeshebeab and Jashobeam. Biblical Hermeneutics sometimes leads us to conclusions we do not really want to reach :)


how to identify the triad on the grand staff?

Question: So basically, I know how to identify triad if there is only one clef, but have troubling identifying the triad when there is a grand staff. Could someone tell me how to do this and possibly give me the answer to the first one?
Comment: It's just a matter of notation.  How would you identify a triad in tenor clef?
Answer: The spelling of the chords is the same. If you know how to read the notes in the bass clef you just find all the notes from both staffs and spell the chord. Doesn't really matter what order the notes are in or how far apart.
If you don't know how to read notes in the bass clef, the two dots surround the line that is an F, hence why it is called the F clef sometimes.
From bottom to top, spaces are A C E G, and lines are G B D F A.
So the lowest note in that fist example is an E. I'll let you work out the rest.
Answer:
I know how to identify triad if there is only one clef, but have troubling identifying the triad when there is a grand staff

I have a feeling you actually mean you know how to identify the chords in close position, but have trouble with open position chords.

Close position puts all the notes "close together" which happens to fit easily on a single stave.
Open position spaces out the notes and requires greater space and fits more easily on a grand staff.
So in close position you might have a chord E G# B and that is easy to read. The starting E is the chord root.

In open position A F# D is a little more difficult. A is not the chord root. To identify the chord rearrange the letters so the tones are all stacked as ascending thirds. The first letter will then be the root.

A F# D rearranged in thirds is D F# A. D is the root. D to F# is a major third and D to A is a perfect fifth. This is a major triad. It's a D major triad.
Answer: You have to notate the notes and find out the third position (that means you have to build a tower of thirds:
example:
A f# d  (the second chord)
a,b,c,d,e,f,g,a,b,c  where can you find here these 3 notes above in 3rd formation?
D,F,A  -> so the chord is d,f#,a
but the bass tone is the 5th
This means we have the 2nd inversion of the D major triad
Answer: Here's a tip that might make it easier to identify chords on the grand staff: the first ledger line below the treble staff is the same pitch as the first ledger line above the bass staff, and that's the middle C. If you place the staves close enough vertically, they form a unified linear pitch space.

Using such "joint" staves your first chord looks like this:


Why human endometrium doesn't stay constant?

Question: Is there any explanation or evolutionary advantage to the endometrium constantly cycling between the proliferative and menstrual cycle? Wouldn't it be more advantageous if it kept always fully thickened? I imagine it is less energetically expensive than to be always producing and losing all those cells, blood vessels, etc.
Answer: One hypothesis is to protect the uterus and oviducts from sperm-borne pathogens.
Also Beverly Strassmann has proposed that the energy savings of not having to continuously maintain the uterine lining more than offsets energy cost of having to rebuild the lining in the next fertility cycle, even in species such as humans where much of the lining is lost through bleeding (overt menstruation) rather than reabsorbed (covert menstruation).