Why would anyone buying regional want to get shot of bases just because they were in England? That just doesn't make sense at all. Especially if they are making money. Scotland just isn't a big enough aviation market on it's own.
No, but if you look at the core routes of bmi regional, ignoring the flying that they currently do for bmi mainline and Brussels Airlines, would it be fair to say that Scotland features quite heavily? Out of MAN you have just
EDI, ABZ and LYS, out of LBA you have
GLA, EDI and BRU. Only EMA doesn't have Scottish destinations dominating the routes.