Without going into too many details, I am still on AFPS 75, but was offered an extension beyond 55 to see out my next (extended) tour. One concern I had was the impact that this would have on my pension entitlement. I wrote to SPVA and sought a written confirmation that my entitlements, inter alia, would remain the same.
It took a threat of a service complaint - and intervention by the CE - to receive a proper written response; the earlier response consisted of a YouTube link, and with a carefully worded 'we don't know'. This is due, in part, to SPVA being hollowed out of both civilian and Service personnel. Nonetheless, if a private pension provider refused supply an account of pension entitlements, I would be off to the FCA in a shot!
I have to say, I still have unqualifiable concerns that I will be migrated across to AFPS 15 for the period of my extension.