Spaz,
I don't think it was reported that Australia's Labor Govt (i.e. Defence spending is not in their DNA) cancelled the option of a further 28 F-35As for the RAAF.
Currently of the contract for 72, about 63 appear to have been delivered. (Ref
F-16.net - The ultimate F-16, F-35 and F-22 reference)
The option for 28 was to take our total to 100, but the Super Hornet / Growler wing will now have to soldier on.