I don't think this will happen in the near future. With the traffic between Canada and HKG so low lately, AC is smart in just operating one flight picking up both passenger from the East and West Coast on 1 plane and then leave for HKG. I don't think there is enough traffic at the moment to justify operating 1 flight nonstop from YYZ and another one from YVR.
Btw, I think the guys over at the CO board are saying that the loadings on the EWR-HKG route are very low.