Army Flying pay is not started until you complete a conversion after wings. Barking.The quickest way to get flying in the AAC now is to fail your lynx or AH conversion and get put onto a Gaz conversion.
I can't speak for the Navy, but this is true in the RAF as well. There are a lot of people on this thread and the other one on AAC pay/FRI/FP complaining that the RAF get flying pay either at wings, or after X weeks of flying training; no longer the case!
Current RAF trainee pilots get initial rate FP
on completion of a recognised OCU, or on recategorisation to B1 if they're first-tourist instructors. So you're not the only ones who get it on conversion! Bearing in mine the lengths of holds that you can still find if you're unlucky, you're looking at 6 months for EFT, 10 months for BFJT, 6-8 months AFT, 4-6 months TW, 6 months OCU...