Hello gentlemen why don’t you just encourage CASA to join the rest of the world and conform to standard ICAO procedures.
Also there seems to be a slight aversion to be negative to your national carrier QANTAS, all I can say here is its very hard to use different calls in every different countries airspace you fly through, so I would suspect QANTAS just found it easier to comply with ICAO.
Also just because CASA has always done it a certain way, dosnt mean they are right and the rest of the world is wrong.
Your AIP can be changed the world wont end.