AC1124 YXE-YYZ shows J0 R0
AC626 YYZ-YHZ shows J7 R6
J = number of business class seats for sale
R = number of business class seats available for upgrades
Ergo you can confirm the upgrade on the second leg right away, the changes of your upgrade clearing on the first leg are very slim as the C/J cabin currently is sold out. (you can always put yourself on the waitlist, and if a J pax rebooks/cancels his flight, your upgrade may clear, but itīs pretty unlikely)