Careful guys/girls!
Unless things have changed recently (but I doubt it), you won't get any BA benefits whilst working for GB as they are a franchise and as such, the company tends to spend as little as possible on their crew in order to be highly profitable! It's no secret!
Yes you wear the uniform but that's all you get! It won't give you seniority or direct entry with BA (if this is what you're looking for, long-term)!
I'm not bitching about the atmosphere, the work or anything like that and I'm sure there are loads of great people working at GB... but I just felt to let new applicants know about the reverse of the coin. So you know...
FJ