You're right of course cats_five, in theory they would only need one or two full cats. However, this is the modern RAF so to make things safer they'll want to show that they're exceeding the minimum requirements and make things as bureaucratic as possible because that's safer...innit.
Anyway, probably not our issue at the end of the day.
In terms of contracts to fly air cadets I think the RAFGSA has been bailing out the ATC for a while.