Where to start . . .


What is the Y class fare for a typical MHD (compared to a J class fare).

If you are not stopping in Canada and are planning to stay in Mexico or US cities on the way for 3 days, then you can get a V equivalent (upgradeable) fare for around $800 plus fees. Full Y is only $1046 plus fees. Full J is only $1300 plus fees.

Which route (from Ottawa to let us say Mexico City) would allow us to potentially upgrade as much as possible on AC:

YOW-YYZ-YEG-YYC-YVR-LAX or SFO (or shortcuts in between) and return of course. Stopovers allowed in LAX or SFO but not Canada on cheapest fare. Stops allowed in Canada on full Y and J fares. Remember even though you cannot stop in Canada on cheapest fare, a stopover on this ticket is 24 hours or more so you can spend a whole day and night in a Canadian cit(ies) provided the total layover is less than 24 hours.

Another thing to keep in mind is that Star Golds have been getting a lot of free upgrades (any fare) on MX flights. We don't know how long it will last, but I have been successful on all my long hauls (MEX-ORD and LAX-MEX) and only once been denied an upgrade on a short-haul. It is an unwritten policy known by some of the staff so you can't point to any "rule".

How much will J class to Mexico City to LA add to the Y class fare on all other segments (on AC)?

If only one segment is in J, the whole ticket will price as J for that one-way portion, ie. if LAX-MEX is in J and YOW-YVR-LAX is in Y, the YOW-MEX fare will be priced as J so you may as well pay J, there is no savings.

How easy is it to upgrade on AC on the following routes: Toronto to Mexico City, and LA to Vancouver, Calgary, Edmonton, or Toronto - on weekdays, and on weekends, for Elites?
-- I never have problems as a SE on these routes (SFO or LAX-YVR, YYC) but YYZ-MEX is often busy. I don't know how Elites fare.