I am not considering taking the YYZ-YQM-YUL-YYC route - it was just a hypothetical. I was quite intrigued by that option given considering the absurd routing. The self-rebooking option only offered 2 out of the 4 daily YYZ-YYC departures that day for rebooking and puzzled as to why AC would not offer all 4 non-stop options before giving such absurd rebooking options.