I think the fact that AC’s significant increase of the “U” fare on this route has something to do with it too. “U” used to be about C$2,500 all-in and many bought “U” instead of playing aerolotto. I used to be one of them. Most of the time, with some advance planning, I can always find "U" availability on this route (outside the upgrade window). “U” is now >C$5,000 at <5% difference with the discount business class fare. AC has pushed this group to either downgrade to play aerolotto, or upgrade to buy discount business class. In the latter case, many have gone to business class of other Star Alliance or One World airlines at much cheaper and better than buying AC “U” to use SWU. I am one of them.