Slitherine

The war is over. Carthage has been defeated and has been forcibly absorbed into the empire. And I have had to sit through a list of announcements as long as my arm telling me that Carthage has retaken a whole string of regions that they had been driven out of and could not possibly have retaken, followed by a longer string of announcements telling me, among other things, that I have re-retaken those same regions.

If that was just cosmetic then it would have been a minor irritation. But it's not just cosmetic. As far as the game is concerned, Carthage did physically retake and then re-lose those regions. What this means is that I have regions that have been under my control since early in the war and which have already suffered the penalties of a lengthy period of being "Just Conquered", followed by lengthy period of being "Under Pacification". Now they are back to the start of being formally "Just Conquered" again even though they have not physically changed hands for many turns.

I've noticed the simultaneous conquer and reconquer messages (as you say apparently a cosmetic bug) but never noticed the reset of conquered status. Sounds like a real bug, I hope Pocus can take a look now that the diplomacy update is out.

I have noted the issue and will check it

It's not entirely consistent. I haven't done an an analysis of how each region is affected, but my impression is that regions that are currently in a state of "Just Conquered" at the time of assimilation probably don't have the counter reset to start again at the beginning of the process, but regions that have been under my control long enough to have completed the entire process can start the entire process again.