Wingswinger
I think you have things round the wrong way. Insurance companies do not buy out on wind up????
A company announces (I might add that I do not believe that this will happen at BA anytime soon) that it wants to wind up the scheme. The trustees consult the scheme actuary. The actuary consults with the market (in fact in the case of BA I doubt very much that the market is big enough for this to happen) and tells the trustees how much money is required from the company to buy out ALL the liabilities. There is no difference between pensioners,deferred or actives. They ALL get annuities bought for them with their widows benefits and RPI etc. This is the law.
Now if the company was bust then that is a whole new ball game.
BA are not going to wind up or are about to close to future accrual. Wind up would be very expensive for the company along with the industial angst just as closure to future accrual would have huge industrial repercussions. No what you are going to get is increase your contribution substantially or except lower accrual - plain and simple.