Ah, apologies if I was being Mr Thicky and misunderstood........
In terms of changes in 2015, my impressions are as follows:
Yes, transference onto AFPS15 will be compulsory - unlike before where you had a choice of staying on AFPS75 or changing to AFPS05. Have no doubt that this is because AFPS15 will be about saving money on pensions.....
Yes, all the politicians and senior neddies are saying that all previous entitlements earned will be retained, so no doubt if you retire post 2015 a portion of your pension will be on 75/05 terms and the rest of 15 terms. I believe they are saying this to avoid panic amongst the ranks, and a mass exodus for the doors of people trying to leave before 2015 to keep their hard earned entitlements under the old system.
However, the exact details of how this mix of pension entitlements will work, and the devil is always in the detail, have yet to be published. I would expect that they have yet to be worked out! 2015 is also some time away, and the wheels of the treasury/MOD no doubt turn slowly.
I hasten to add that I don't work in MOD or the Treasury!