Thanks for the replies that you chaps have offered - very helpful.
In my case I had a letter yesterday saying that my RAF pension would half as a result of this adjustment!
Since I knew that there would be a reduction I was almost prepared to accept it, until you chaps on PPrune stimulated the little grey cells. After reading the above posts, this morning I phoned them up.
It seems that in some cases there is a 'glitch' in their system and I was one of these 'glitches'. They have promised that they will get it sorted out, and the reduction should amount to as little as £20 per year. At today's prices the loss of 5 pints p.a. is something I can live with.