Fairly senior Flt Lt (lvl 7) on £44,058, on Enhanced rate FP of £16,147, total pay just on about £60,000.
Sqn Ldr Level 1: £47,760
"Well done Flt Lt Bloggs, you are a snappy dresser and all round good egg, and therefore you have been promoted to Sqn Ldr. Go immediately to the IPT/MAA/JHC/Head office/{insert your choice of ground tour here}, oh and as its not a flying tour, take a £12,000 pay cut, what do you mean you don't want to?".
There is obviously a need to save money, and a lot of it, but a 20% pay cut for your best officers on promotion just doesn't seem like quite the way to do it?