This is a bug that I've encountered a lot and somehow couldn't find a bug report about it.
Basically, if you cast Fane's Time Warp skill on a character who postponed his turn, after this character's first turn the battle will be stuck. Everything will show that it's still this character's turn, but he won't be able to do anything besides escaping.
If you save/load the game at this point, the battle will continue from the next character in the queue and your character will still possess Time Warp status.