BigBadDon & grace,
I have my FB next week, if you research BA via both their website, appropriate magazines such as Flight int. and Airlines monthly e.t.c. and also in newspapers so that you have a good foundation knowledge of strategies, fleet and business that should help. In addition to this as many people have probably said, be yourself! Try to have a couple of examples other than your application examples of team working, leadership.... There is also a book which deals with interview questions which will help your general interview technique, title is something like 'The toughest interview questions answered.'Bright red cover! Sorry I cant be more helpful.
I may be the person Mister Geezer was refering to, e-mail me and we can help each other. United we shall stand!