Ok a very simple scenario ; a Night VMC pilot without IFR equipment or rating is at about 15 nm north of Hobart at about 5000' . He could be inbound or outbound or simply crossing the airspace.
How does ATC in the Melbourne Centre provide a class C separation service to an IFR airline aircraft , also to the north , either inbound and outbound ,if the airline aircraft is going to be at about 5000' at 15 nm at the same time?
No , not a trick question - just a situation that could easily happen!
And what's the separation standard required as they pass through 500' of each other?
Fujji. That's before I made the AMATS changes and you would have been given a traffic information service at Ayers Rock in class G. Very different to " upside down" class C at Hobart.