They are using YXU as an alternate airport. WestJet used to run seasonal mainline YVR-YXU-YHZ, so they know the load factors. Guessing will be more profitable on Swoop. I'd be shocked if it remains year round though. YXU is within driving distance to lots of Southern Ontario locations. People often underestimate the size of YXU catchment too due to it being 1.5 hours out of YYZ. Metro CMA is over 500,000 and it draws traffic from Windsor, Chatham, and Sarnia. If not for the proximity of YYZ it would be a lot larger than it is.