Consider flying china eastern, if you are not particularly concerned about status or upgrades.

From what I understand, there are flights available for $550-600 to PVG from YVR most of the new year and maybe even now available from www.flychinaeastern.com (I was searching on the HK English side and just converted the HKd to CDN$. But I assume it's the same on cdn website).

The one main downside is they don't give miles, oh and not necessarily personal tvs. Also their English is somewhat limited, but I can live without in flight fluent announcements. Service is otherwise much friendlier than AC.

Maybe that's why AC is canceling flights: can't compete on price.