I'm not aware that other provinces have a regional distinction the way it was set up in the province of Quebec. I know in the province of Quebec they do have census economic regions and health regions, as exist in other provinces.
It would be a policy decision that I'm reasonably sure the Canada Revenue Agency could administer, but they would need to know precisely the definition of the regions. Quebec can perhaps maintain their regions, and we can use other regions in other parts of the country, and we can neutralize it. I'm sure there are different options. I'm sure once that was clarified, the quite capable people at the Canada Revenue Agency could administer it.