in recent times has been increased by a further £4k (albeit non pensionable) as a good will gesture by BA in 2007
Not quite a good-will gesture from BA actually. It was paid for by moving the annual pay 'cost of living' rise from October (when most BA employees negotiate) to February thereby giving 1/3 of our annual 'pensionable' pay rise back to fund a non-pensionable increment! It was another of BASSA's monumental failures that, not only did they not cost out whether it was a good deal but they didn't ask us whether we were okay with it either. So you could see it as a goodwill gesture to the pension fund from BASSA because it has reduced the pension liability.