But they do have full ADS-B coverage.
Groundloop,
Where ever did you get that idea.
The coverage is high level only, and strangely, where it is available low level , it seems that ATC do not use it where SSR/Primary radar is available.
There are no formal plans to extend ADS-B coverage to low levels across the country, even though CASA is now suggesting mandatory ADS-B even for VFR post 2019. This despite Government/CASA "policy" for risk based regulation and cost/benefit justification.
Given the major losses recently announced by Airservices Australia, and the shambolic state of the OneSKY plans, budgets and execution, wait for the Senate inquiry "real soon now".
Tootle pip!!