Many left the Rn before the rules changed giving a preserved pension at a certain age to those who left before completing 22 years service.
I believe that the rules were changed sometime in the 1970s.
Those who left the service before the date of the preserved pension rules changed got nothing. My wife served for over six years due to the date of her leaving (1970) is entitled to zero.
STATEMENT OF INTENT
Our aim is to secure equality of pensions for former regular members of the Armed Forces who served for fewer than 22 years at any time to April 1975 and who were discharged before 5th April 1975. This also applies to those regulars who were discharged prior to 1981 who do not meet the criteria of length of service and age. We ask Her Majesty's Government for pension rights based on years of service and related, pro rata, to pensions received by contemporaries who completed 22 years of service..