This is an interesting question WWW, mainly coz I am also unsure! When I instructed there were no restrictions, and instructing on the RAF scholarship thing, good job too!
Even as a 509 instructor we had no duty/flying limitations, and I am pretty sure it is still the same, maybe JAA will change things though. In reality, to get anywhere near the max is going some. As a 509 instructor I did 80hrs a month for 3 months in a row, (good bonus!) but that was 6 days a week from dawn until dusk, with all the pre flight and post flight briefings, very tiring. In the mean time, fill your boots mate, no one is going to stop you at the moment!