The current thought process I have is that the 24 hours thing applies to Ulti's role after his death. XIII looked incredibly awful yesterday and was doing nothing but arguing with me. Mafia has no reason to kill him, all he was doing was distracting town by being an idiot.(I don't care if he justifies that play as part of his plan for the game.) So XIII was more than likely killed by an independent, which was a bad kill on their part because it reveals they're in the game as far as I'm concerned.