I think it's a mix of Wisconsin(More Western UP) and Canada(Northern Lower or Eastern UP)
I’ve never known anyone who pronounced “about” like “ah-boot”. The (to my mind) standard Canadian pronounciation would be (close to) “ah-boat”, as opposed to “ah-bowt”. OK, that’s not strictly true, I’ve heard Scots pronounce “out” (for me it’s closer to “oat”) like “oot” and “about” like “aboot”, but Canadians don’t speak like Scots, although there was a large Scottish influence in parts of Canada.