My experience has been the same as that of the other respondents: the
node name used when the scheduler service is created is frozen in. I
have always ended up having the system administrator delete and recreate
the service when Windows nodes have been renamed at our site.

There is another issue you will need to deal with. The node name for a
Windows client is embedded in each of the file space names corresponding
to drive letters (but not in the SYSTEM OBJECT file space). You will
need to rename the file spaces to match the new node name.