We still outlayed A$ 6.6 billion, regardless.
And some of that 6.5 billion can be spread across future purchases of Super Hornets as it is infrastructure et al.
Yes, we did, but about $3.4 billion of that would have had to be spent on F/A-18Fs, or F-111s (at least!), or JSFs (had they been on time) regardless.
The infrastructure being built for the Super Hornets - new squadron HQ, maintenance hangars etc - have all been designed with JSF in mind, i.e. they have the necessary compartmentalisation for the increased security required on the JSF (and the Rhino), so they will not need to be redone when the JSF finally arrives.