Originally Posted by winnipegrev

1) They are all safe, even the older aircraft have tons of cycles left on them.
2) AC won't schedule fins until a few days before, and they are swapped usually several times before the flight as flights delay/cancel for maintenance/weather elsewhere in the network up until you actually board the aircraft.

"May I have your attention please. This is a gate change announcement for Air Canada, flight 894 with service to Milan" etc