I think to most logical acquisition is buying Virgin Australia...

I think to most logical acquisition is buying Virgin Australia Regional Airlines, which operates a complementary FIFO business in Western Australia. As AQZ already has ACCC approval to operate a JV with VARA, I assume a purchase would be more straight-forward to get past the regulator than some other currently non-aligned operator.

AQZ haven't been keen to push into RPT services in a big way. Such operations have a much different risk profile that charter and wet lease flying. For those reasons (plus I assume that they have already passed up the opportunity), I don't see purchasing AirNorth as a high priority. As for needing to think about a replacement for the Fokker Jets, I came across the following in AQZ's prospectus issued in 2011 when they listed on the ASX:

While we are now 9 years on and presumably the number of cycles on the aircraft still owned has increased by about 10,000 per aircraft from the average cycle numbers listed, there is still plenty of cycle life left in them yet. AQZ have also been active is securing a large store of spare parts. While there will be newer aircraft that are far more fuel efficient, the capital cost of a F100 and the depreciation per hour of flying will be a fraction of the cost of a more modern aircraft. So provided the Fokker's remain stay reliable and customers are prepared to use them, I see them flying for a long while yet. AQZ regularly proclaim industry leading on-time performance.

I wonder with the surplus aircraft that have been parked up globally over the last few months whether there is an opportunity to apply the AQZ model to purchasing and operating some different low cost aircraft in some other overseas markets. One of AQZ's founders (and a former director), Hugh Jones, developed a successful business with Airwork in New Zealand to purchase 737's, convert them to freighters and operate them on behalf of freight companies like Toll. Not sure how competitive that market is but I'm confident that AQZ's management would have the track record to make it work.