Required reviews completed I have submitted a paper and I received a request for major revisions. 

The first time the status changed from "under review" to "with editor". 
After that I submitted a revised version of the paper. Now the status has changed from "under review" to "required reviews completed". 


Why first time it wasn't shown this status? 
How many days does it usually take to change the status from "required reviews completed" to next status?
Most likely this means it has passed to the associate editor to decide what to do with the reviews.  In my experience the deadline for that action is typically about a week from the time the final review is available, but of course if the editor is otherwise occupied, it might take a while longer.  Patience!