As to your ticket from Australia, if I knew which way ticket prices were going in the future, I would've retired earlier from the airline industry. I may be speaking out of turn, since I have never flown to or from Australia. It may be the case (and you'll have to read the fine print) that your ticket is not refundable, but maybe exchangeable. In other words since Covid some airlines in the US give flight credit not refunds if your flight fare lowers before departure, unless you bought a basic economy seat. You'll probably have to fight for it. But do stay on top of it. I suspect closer to departure time, unless your flight is sold out, there may be price fluctuations.