As I said in an earlier post the GMB has had recognition rights for cabin crew for at least 30 years. They had a branch at one time but it faded away.
They are a very large union and already have considerable membership in other areas of BA and seats at BATUC and all other major forums.
The lady mentioned in an earlier post is NOT cabin crew but a full time official of the GMB with the role of Regionall Organiser. This is normal all unions have organisers who try and get membership and then representation within companies.
BMI were represented by CC89 and were the second airline after BA to join in 1989. They have a structure and reps who are now Unite.
I would hazard a guess if GMB is successful a lot of them would join as they are not BASSA fans.
I very much hope this venture is a success and that cabinCrew get a decent union again.