Think I agree with many of the comments posted. My experience has been good loads (or oversold) on this route. Why spend marketing dollars on a route that does OK for AC?

Even though it means more time, my preferred travel is to go via HKG, rest up for a day , then continue on -- avoid old planes on the direct route as well that way. I always have had better luck getting flights for the dates I wanted out of HKG than BJS or PVG even though I did miss upgrades twice on the HKG-YVR route (the only time I have ever missed upgrades on AC!).