My wife and my mother-in-law are going on a flight to MCO from YOW tomorrow; They are on the same reservation. My wife is an E75K.

So they have been upgraded.


My sister-in-law is on the same flight, but different reservation.
Can my wife upgrade her (subject to business class cabin availability and the priority of people on the upgrade waiting list) as well?

I know that if the first passenger can upgrade another passenger not on his/her reservation, at the airport. I am not sure if this is possible if the first passenger (as in our case) the companion on the same reservation, as to whether this other passenger (as the third passenger) can be potentially upgraded?

Here is an excerpt of what Air Canada web site


All Altitude members can also request an upgrade for one companion travelling on either the same reservation or the same flight. You can make these requests at the airport on the day of departure.