Would be really nice to be able to talk to CS Appr in the circuit though! I know that's a lot to ask, but hell, its only 26 nm from Cairns!
There's a lot of big hills between ATN and the VHF site at Saddle Mtn making line of sight impossible, unless your cct is above 4000 ft
- Approach can see your transponder in the circuit from the Hann Tableland radar (NW of BIB) so any problems it's Brissy centre on 124.6 or squawk 7600.
Good luck on the CASA approval.