my present network configuration is:
in main office - 3 servers with NetWare 6.0 + SP5, on one of them runs BM
3.7 + SP3, eDirectory 8.6.2
in four branch offices - one serwer running NW 6.0 + SP5 and BM 3.7 + SP3,
eDirectory 8.6.2
All these BM servers are connected to main office via vpn in full mesh
I have to upgrade all my NetWare serwers in main office to NetWare 6.5, so
I have to also upgrade BM 3.7 to BM 3.8.

What is the best procedure, to do it without loosing vpn connections?
Can I upgrade servers only in main office and leave servers in branch
offices running NW 6.0 and BM 3.7?