Arriving at YYT, our priority bags are never first off. But it's usually the only flight and only an A220 so it doesn't matter so much. I have never seen priority bags get priority with AC.

I was recently impressed with UA when flying YYT-(AC)-YYZ-(AC)-SFO-(UA)-BUR. Upon dropping my bag with AC in YYT, I got a text from UA with information about tracking. Then from SFO through BUR I could see exactly when the bag was scanned on to the plane, and put onto the carousel. It came out first. Really shows how bad AC is by comparison.