Anyway it's crazy. JQ can operate to 0.1 RNP minima in ZQN, but are still restricted by the regulator to 0.3 RNP in Aus.
Everytime you do an RNP AR approach, you submit paperwork regarding the performance of the aeroplane etc etc.
The technical Pilots pull the data from the approach and use it for stat building to support the case of reducing the RNP value.
Queenstown has been operating for some time, hence the RNP 0.1 approach criteria. RNP AR in Australia for Jetstar is relatively new. It will take lots of approaches and proven equipment reliability, plus ongoing simulator training and data assessment before the regulator will give approval for reduction.
It's just like ETOPS. The aircraft may come out of the box with the approval, however the operator has to build their experience before increased approval is given by the regulator.