Wenger is an exceptional case and I also think that Arsenal fans aren't worried half their team will leave. If Mauricio was definitely seeing out his contract, the board would have made an announcement to that effect to stop the rumours.
Maybe he is, I can't think of many other managers who stay in a job long enough for their contract to be renewed, but Arsenal have sold plenty of players recently.
I'm not sure the board would say anything, didn't someone (Reed? Krueger?) recently say something like "I don't understand all the fuss being made - Pochettino still has a year left on his contract."?
EDIT: Moyes's Everton contract had almost run out when he decided to take the Man Utd job so there's another example.
