I think FJTS is entering into some sort of arrangement with 17(R) Sqn - don't know if this is how they will end up badged, but there seems to be a bit of OT&E v DT&E and 'what do TPs have to do, and what can OEU pilots do' debate going on (thought we'd sorted that about 5-10 years ago....)
Seriously though, have you tried the Air Historical Branch? They should have the official date at their fingertips.