I would have thought the simplest thing to do would be to have every employee under the BA "umbrella" on the same contract. By that I mean any company which is wholly owned by BA. Obviously GB, Bmed, and Maersk do not apply as they are entirely separate.
One of the reasons that BA has so many problems is that it has too many people on different T's and C's, thereby leading to division and "scope clauses".
The basic premise is sound enough as it should prevent "contracting in" cheap labour, as per the merchant marine. However, within the same company it does start to become ludicrous.
If you are employed by BA then you should be on the master seniority list and paid the going rate. I suspect that it just won't happen as too many people have their own agenda, especially those within the BACC.
Remember, anything outside LHR does not exist as far the BACC is concerned, and that means everyone at LGW and BAR.
To those at BACX, welcome to BA, how do you like it so far?
Harry, citizen of the Republic, second class.