Personally I think it's a wise decision to delay, it would be better if we cut it away all together. There are several gen 4.5+ aircraft that I think would be a better fit for the RAAF, the F-15SE Silent Eagle and the Super Hornet with the International Roadmap improvements to name two. Both are proven designs that provide 80% of the F-35's capability at half the price.
Does Australia actually need the capability that the F-35 promises?