Gentlemen
I have no knowledge of the letter to which you refer, but I can tell you what JSP 754 (Pay and Charges) has to say about Specialist Pay (Flying).
I am afraid this is one area where, despite being a tri-Service document, it allows differences between the 3 Services, however:
Pilots not qualified as Aircraft Commanders (P2):
RM/Army (Officers and ORs) Pilots P2 - SP(F) at Initial Rate "On completion of CTT"; Middle Rate "After 9 years' total service, subject to a minimum of 3 years' aircrew service; Top Rate "after 18 years reckonable service".
Officers: Maj and below, Upon qualification as Aircraft commander (P1): P1 SP(F), Initial rate "On qualification" (as P1); Middle Rate "After 4 years on the preceding rate"; Top Rate "After 4 years on the preceding rate"; Enhanced Rate "(on having) Received the top rate of SP(F) for 4 years.
Other Ranks: Army NCO pilots qualified as Aircraft Commander (P1): P1 SP(F), Initial Rate "On qualification as aircraft commander"; Middle Rate - "After 4 years on the preceding scale"; Top Rate - "After 4 years on the preceding scale"; Enhanced Rate - "Afetr 4 years on the preceding scale".
RM/Army - Transition to P1 Pilot Status
On attainment of aircraft commander status, RM and Army P2 Pilots will transition to the P1 scale as follows:
Pilots on P2 Initial Rate will transition to the P1 Initial Rate with zero seniority in this new rate, i.e. they will then have to serve 4 years on the P1 initial rate before elevation to the P1 Middle Rate.
Pilots on the P2 Middle Rate with less than 4 full years seniority on the P2 Middle Rate will remain on the P2 Middle Rate until they complete 4 full years on that rate, before transitioning to the P1 Middle Rate (with zero seniority at this new rate).
Pilots on the P2 Middle Rate with 4 full years or more seniority on the P2 Middle Rate will transition immediately to the P1 Middle Rate (with zero seniority in this new rate).
Pilots on the P2 Top Rate will transition immediately to the P1 Middle Rate (with zero seniority in this new rate).
From what you have been saying above, you appear to have been told something different. Or have I misunderstood? I cannot guarantee, of course, that a change to JSP 754 is not in the offing.
Regards
Ginseng