That does appear to be a problem if you skip the turn of a player character immediately before the character that is sneaking has their turn. When I first tested my rogue went first, so this wasn't an issue, unsneaking with the rogue and having the mage sneak replicated this problem. It shouldn't be an issue when there are other NPCs between skipping a turn the start of the sneaking character's turn, though.
I'll create a bug report for that.
