Originally Posted by FlyerJ

In fairness, it’s super tough to schedule long haul (really long!) eastbound flights like these any differently. Not only are they super lengthy flights, they cover three time zones — losing 3 hours on the outbound. Total flight time plus time zone changes only leaves a limited window if they want to run the flights during daytime. The only real other option to do these - each using a single aircraft based in YYC - and with timing that would allow for more than just very short-haul, regional connections at YYC: run one segment as an overnight flight. That would be awful (IMO, any redeye not crossing an ocean is awful) and incredibly unappealing.