The Virgin ATR's?
Hevilift Australia - operate one or more, established operator, AOC, if time are quiet could always move one or more to PNG, where they are an experienced ATR operator, albeit different model.
Regional Express - would need to upgrade the AOC to high capacity or comply with new Reg coming in around December. Plenty of experienced flight crew to assist with T&C qualifications. Would need access to SIM
Qantas - Never, they have a very successful Dash 8 operation, don't need another type in the fleet 80 knots slower than a dash 8-400. Would need access to SIM
Sharp Airlines - possible contender, very astute businessman, could run a nice Adelaide, Mt Gambier, Portland, Warnambool, Melbourne, Canberra, Sydney scenario. Would need access to SIM
Pionair - too much on their hands with Kiribati E190, SIM required
New start up operator - Not likely, CASA has advised that the new Regs and December workload make this impossible before mid next year. Would need access to SIM
Not sure where the closest or most practical ATR Simulator is but Covid will make travel impossible unless in Australia.
..