Wow - that's taken a long while to come to market, guess it was held up in the courts. I thought all of this finalised maybe 8 years ago.
Sounds like it's the collection formerly owned by Steve Hart. He ran a large accounting practice that did a lot of dodgy tax work. Cost the ATO > $200m.
He battled the gov for years, but eventually, as the song goes "... I fought the law and the law won ...".
Interesting thing if that all of these aviation assets had been put into an "aviation museum" trust, but I guess the courts saw thru this and grabbed the lot.
In the end I think Steve got done for peripheral charges like insurance fraud. He was 4 years into a 5 year sentence when the gov came back with more charges - which is a sign the gov is really out to get you!