Fabric OS v7.2 issues

[Anonymous]

I have recently had to upgrade an old, but stable SAN40B fabric from v6.4 to V7.2 to get a compatible ISL with a new SAN24B (IBM badge) FC switch running V7.2.1.  I am using the CLI to upgrade.  The upgrades went well up to v7.1.  On loading V7.2.1.c, 2 of the previously working ports with NPIV connections went offline with the error "  Mapping error:  ports already FC".  One of the ports came back online, but not with ALL of the NPIV connections.  The 2nd port is online and shows a healthy phsical connection, but no NPIV connections.  Has anyone else seen this behaviour?  IBM support is clueless at this stage.