bealine,
For Flight Crews, those with contracts prior to September 2003 will be under BA Mainline, those who joined after will be "BA Gatwick and the Regions".
Bolleaux, I'm afraid. All mainline flightcrew are on the same contract irrespective of date of joining or base. Some are on secondment elsewhere (BACon as was and GSS) but their contracts are all the same.