I assume the local papers and radio will have covered this? If not, prod them!
Ask what development is planned, the costs, the time-line, what progress has so far been achieved, what revenues have been raised by the existing ADT, and where the revenues have gone.
These questions should also be raised to Norwich City Council. Following that, start a "Don't Fly From Norwich" campaign and tell the local press and radio. They'll love it (I'm speaking as an ex-Local Radio News Producer). That will start loads of letters and phone-ins. Questions will be asked. Before it all gets too embarrassing, they'll repent and return to the more modest fiver. However, if they have merely offset the income against costs NCC will as stake-holders be complicit in misrepresentation of the fees' purpose. Oh the joy!
Suggest big banner at the next televised Norwich City footy match saying "Canaries Don't Fly From Norwich."
Trust me - I used to be very good at this!