I now have done that x number of times, so I know I did not make any mistake

Existing eDir group called 8 with added GW account
The 100 members are correct

In C1 I can see that is all correct, but in GW client Address Book the
members are COMPLETELY wrong (they are different student year)

I even re-created the group from scratch & in Address Book still have the
wrong members!
Also re-synch number of time, no difference

C1 membershit is NOT the same as end client Address Book membership