Because I was looking at the period around WA's school holidays in April 2020, I looked at DPS. The Premium Y TransPacific fares were almost as good as exSIN, noting that DPS-HKG is on a regional plane without PremY.... And there are 3 Jetstar flights a day PER-DPS with plenty of alternatives if JQ becomes "greedy". The QF flights PER-SIN were already approximately AU$700 outbound around the dates I needed....
Now to which airline do I post the long haul flights?
Happy wandering
Fred