You're right - I recently tried it by flashing the XAC CSC version and it was a lagfest - a lot of notification bugs too, but also 5G did not work (which I am guessing is due to CSC specific modem firmware).
I haven't seen anything like that. Canada is a small market, I would say it's risky to go down that path while keeping the Canadian software.
You may have to manually enable file permission. Sometimes you get 3 options and it defaults to the middle which is not full file access.