This may be a long shot, but it's worth mentioning. When I used to fly Air Transat when it routed YYZ - NCL - YYZ I always found it full. However last year I was slightly put off by the fact that it routes via EXT and had to disembark and go through security at EXT all over again. Maybe this could be an indication as to why the Pax numbers fell, as most people chose to fly Transat from NCL as it was direct. Just a thought.