ibid or Ibid (Capitalisation)? ibid or Ibid?

Context:

In my efforts to use footnotes for the first time in my essay, I've come across a few problems (which you might know if you've seen Part 1 of the ibid journey.
I recently read online that it makes a difference whether you use ibid or Ibid (capitalization) in your footnotes and that there are even rules around this, at this site (I don't go to the school running this site).
They say:

‘Ibid’ should always be capitalized when it appears at the start of a footnote. If there is a pinpoint reference, that is, a reference to a specific place in the cited text, and the next footnote is to the same work and to the same place in the cited text, use ‘ibid’.

But, isn't ibid (or Ibid) always at the start of a footnote, so shouldn't it be always capitalised?

The Question

When should I use &quot;ibid&quot; or &quot;Ibid&quot; in my text? What difference does the capatilisation make?
Ibid is not a proper noun, so it's not capitalized as a matter of course. (Your own question contains several examples where lowercase 'ibid' is used correctly.) Whether it should be capitalized at the start of a footnote depends on the style guide used. For example, OSCOLA uses lowercase 'ibid', whereas the Chicago and Harvard styles use the capitalized form. When used for in-text citations it is typically lowercase, however.
Finally, when used with footnotes, 'ibid' doesn't necessarily occur at the start. In books I've seen 'ibid' occurring after parenthetical remarks, such as &quot;For X, see ibid p. 50&quot;. Sometimes a single footnote is also used for multiple references, as in this example from the Physical Review style guide, where 'ibid' refers to the journal name:

J. M. Smith, Phys. Rev. B 26, 1 (1982); R. Brown, ibid. 24, 3 (1981); C.
Green, ibid. 24, 22 (1981).