Tim,
Long story short, to make things simple, you would want to keep your NEW master the same name as the old master. It is a pain to try to change your master server name. This is typically something you would want to engage Symantec support with.
Here is a recent forum post with some suggestions for upgrade:
https://forums.symantec.com/syment/board/message?board.id=21&thread.id=35125
Aaron