This has (would be? see edit below) actually been a loss in capacity and frequency for the YYZ-YFC route. It really limits connection opportunities (super long layovers for international evening flights) and makes a daytime round-trip to Toronto for a meeting nearly impossible.
YYZ-YFC used to be 4x Q400 = 312 seats
Now it's 2x A319 = 272 Seats
Edit: I'm now looking flight statuses and it seems AC has gone back to 4x Q400 on this route, when I looked a few months ago it was 2x A319 after June. Did they delay the implementation or go back to the old schedule!?