We (the Forces Pension Society
Forces Pension Society - Fighting for the Forces and their Families ) produce a useful fact sheet for our members on this as there are a lot of rumours about the extent of the DWP reductions. In a nutshell, there are two separate adjustments: the GMP and the National Insurance reduction.
The GMP element (the non-increasing part of the Armed Forces Pension) is applied only when the State Pension is put into payment, not when one reaches the State Pension Age.
At State Pension Age (whether one draws their State Pension or defers it) there is a small NI reduction adjustment annually.