AK1, nice of you to include YQB in your MR plans, but you should know that AC8600 and AC8603 are usually operated with CRJ so no possibility of getting upgraded to J; accordingly, you'll most likely only get 250 Q miles per segment.

Your 31 minute turnaround at YQB won't be a problem as you'll deplane at Gate 7 and then re-board at the same gate. However, weather can be a real concern at this time of year so any delay in leaving YYZ on 8600 or on the 8603 return leg can start to chew away at your connection time for your final YYZ-YVR flight at 1500.

Good luck !