You can use eUpgrades on an AE ticket within 24 hours. That is the window period for X fare - 24 hours. There is a copay ($250 on this route).

I did this in December for YWG-YYZ-YOW. I was waitlisted and both upgrades cleared at the gate. I was top of the list for both segments, but that will depend on status and how many other people of that status are flying.

In my experience YYZ-YVR is difficult to upgrade even several days out, however YMMV.