1. What is the best way to confirm the upgrades? I am flying out on April 11 at 9am. Should I call Aeroplan on April 8 after 9am to confirm the upgrades? Will they be able to confirm and allow me to select seats?
Call just after midnight on April 8. Not really 72 hr but 3 "days"
Yes you should be able to confirm/select seats
2. On the return trip. The city of origin is ICN, but I won't be upgrading that flight. What are the procedures for upgrading my connecting flight? Will the check-in agent know what to do for my upgrade on the domestic flight? Will it better to ticket the domestic flight in YVR?
do the same--phone (Canada time) 3 days advance. Confirm etc. If flying on AC all the way they should be able to issue all boarding passes if continuous travel, including upgrades.
3. What are the chances for upgrades based on the current availabiltiy. J9 C5 and J9 C0?
C0 not good but J9 C0 indicates probably still OK but may have to standby at gate. Those sorts always clear for me as SE.
4. Are the upgrades chances usally good on YYZ-YVR, YVR-YYZ flights?
Someone else can answer that-- I am sure some flights are mostly full, others not.
5. Is there anything else I should know about using upgrades?
2 Elite certs for long-haul but it is origin to destination in N. America no matter how many segments provided there are no stopovers.