Thank you THPP, this is very much my thinking at the moment.First up, things seem fairly normal here, pretty much as relaxed as at any time in the pandemic. The numbers clearly indicate otherwise tho.
A friend of mine managed a round trip in Sept-Oct flying Sydney - Doha - London on Qatar Airways. So under current rules it's certainly do-able. But future restrictions are unknowable. France literally overnight just scuppered the Christmas plans of thousands of travellers from the UK. The Aussie government may similarly get spooked by the numbers coming out of the UK and pull up the drawbridge again. And though the UK government is unlikely to take the hugely unpopular step of cancelling Christmas again this year, it may well move to some kind of Plan C in January, maybe even a limited lockdown. Like I say it's unknowable. Tho it is guessable based on past events.
If it were me, I'd be inclined to put my trip off for a couple of months. By then Oz will be coming out of its low number Summer and the UK numbers should be greatly reduced as the effect of the mass booster jabbing exercise kicks in.
Good luck with your trip, whatever you decide