That image is the district of Alberta. Alberta joined confederation looking like it does now by combining woth the district of Athabaska.
1905 – The provinces of Alberta and Saskatchewan are created out of the districts of Athabaska, Alberta, Saskatchewan and Assiniboia; the District of Keewatin is transferred to the newly defined Northwest Territories
True, same is true for Quebec if you check the 1905 map, however what they would get upon separation would be somewhat similar to the yellow portion here, though I think some of the northern part of that yellow portion they lose as well.
It’s not the same as Québec because they joined in 1867.
The big point is that the “borders at the time of joining confederation” would give them the whole slice. Thiugh I agree it is unlikely they get the whole slice, and the entire thing would be a protracted international legal battle with border disputes for decades.
The funny thing is, if Alberta were to separate, it would likely mean the same thing for them as Quebec.
Namely, you get the part of your province you joined confederation with, not all the northern crown land that was added to your province afterwards.
If Quebec separates, they lose everything from Val d’Or and north.
Alberta would likely lose Fort MacMurry and possibly Edmonton… I need to go dig for that original map of their pre-confederation territory.
EDIT: Its hard to find a good one, but this is the area they had before the new province was created as part of confederation.
https://www.canada.ca/en/canadian-heritage/services/historical-boundaries-canada.html
That image is the district of Alberta. Alberta joined confederation looking like it does now by combining woth the district of Athabaska.
1905 – The provinces of Alberta and Saskatchewan are created out of the districts of Athabaska, Alberta, Saskatchewan and Assiniboia; the District of Keewatin is transferred to the newly defined Northwest Territories
True, same is true for Quebec if you check the 1905 map, however what they would get upon separation would be somewhat similar to the yellow portion here, though I think some of the northern part of that yellow portion they lose as well.
https://en.wikipedia.org/wiki/Partition_of_Quebec
My point being, there’s a strong likelyhood they would not walk away with the whole province.
It’s not the same as Québec because they joined in 1867.
The big point is that the “borders at the time of joining confederation” would give them the whole slice. Thiugh I agree it is unlikely they get the whole slice, and the entire thing would be a protracted international legal battle with border disputes for decades.