I was a civil servant 1973-2003 but my 12 years RAF service 1961-1973 did not count towards my civil service pension because I left the RAF before 1975.
Yes, despite the MOD-appointed Grigg Advisory Committee on Recruiting recommending in 1958 that service pensions be made transferable to other Government employments.
The Government undertook to look into that recommendation, but oddly enough never reported back to Parliament on that point.