Rosencrantz
Very well known Exeweb poster
It changed as you described for HMRC employees in 2015, I know that as I have one month's worth of the new pension before I left.Pensions for public service employees were altered around 5 years ago iirc(if under 50 iirc)
They went from Final Salary to Career Average which I believe is not so costly,but of course not quite as good as FS (perhaps one of the financial gurus on here can confirm ?)