Greetings WSA,
I am neither IB or BA, but do follow their moves with interest. Both companies are operationally independent, so no cash from one to the other, least of all for pension funds.
BA is making money from its own operations, as its yields have been improving. IB is losing money and thus having to use up its cash reserves.
The thing is, BA had some tough times (remember it parking a few 747s?), and has been recovering (747s are back, with new first class), whilst IB had not had it as bad (not least as its competition has been more limited on long haul) and only losing money on short haul ops.. But things have changed with the Spanish economy in bad shape, more competition (KL-AF and LH have added routes and capacity to LatAm) and high fuel price have derived in overall losses for IB. The bad times have now hit it.
In my view a good solution for IB would have been to come to an agreement between management and staff, as BA did with theirs that allow lower costs on certain operations (For instance now BA can use 744 to Moscow and back with the same crew, whereas before such a thing would have meant change of crew at Moscow with accommodation costs for 14 people).
As for growth at LHR, you will find that BA will increase its long haul significantly with some slots it has acquired (some leased, some bought), and soon with bmi and all the slots that come with it. BA ordered A380s and 787s a few years ago for delivery from next year, and they will come in handy. For the moment they will have to do with 77Ws. A number of long haul destinations will be added over time.