The only way they would give approval is for rocketry operations. They would not get approval for model aircraft to fly above 400 feet except by application to CASA, NOTAM etc... Cost = $$$$'s
Rocketry operations are really the only exemption that you can get but they must be approved in very small windows, Notam etc. required.
Rocketry is very different to model aircraft.
note: there may be some legacy approvals in place as you have mentioned above, but I know since all of the new regulations were introduced it is not going to happen now.