Study Permit First and CAQ later

I have one urgent question below.

We are from Malaysia. My son Bryan has got 2 offers,from UBC and McGill. At first he decided to go to UBC, so he has applied for Study permit using UBC acceptance letter. But later he changed his mind, he wanted to go to McGill, can he go to McGill after he has got his study permit to study in UBC , and PLUS a CAQ letter obtain later from the Quebec Immigration Office. Is there any other application he needs to make in order to study in Mcgill?

Please help. Thank you

I know this is late, but I hope it can still help. A study permit is only good for one school, he’d need a new one to go to McGill. Also, to gain a study permit for study in Quebec you must send a copy of your CAQ (there is one marked Immigration Canada) with your study permit application. Thankfully CAQs have a fairly quick turn-around time; I got my CAQ in around a week and a half, my study permit took almost three months