I travel AC out of HKG a number of times a year. (or did still I started buying cheap J fares)
In my previous life, I used to upgrade as SE. YYZ was tough (I always got the J seat, but sometimes not till 40 minutes preflight. YVR is much easier.

With either route you need to know that their likely is atleast 1 SE and 5-8 E's trying to upgrade. YYZ as a P would be unlikely in my experience, but YVR could happen.

YVR is likely to be the crap A340 though.. almost not worth it. I think Y and an empty seat on the 777 is 'almost' as good as J on the 340. Y on the 340 is hell.. I had to do it once..with 3 empty seats next to me (middle 4 seats) and it was almost beyond hell.

If you check bags, you will not have to go ground side, just hit the transfer desk.. If you land by 11:00 you'll be at the transfer desk by 11:20 latest.