Are there really any overly majority unionist areas? I don't really think so, and no the SNP would not allow them to remain in the U.K. Scotland is Scotland theres no divide like there was in Ireland. Plus it is very impractical to break up Scotland into areas and say here you guys vote on independence based on council areas and then we have some staying in the U.K and some not.
Yes or something like it, maybe every 15,20 years