No, the opposite.
Because there is a great demand for seats, esp in premium cabins, if you don't jump in fast, the points required will most likely go up, so to speak/proverbially speaking.
What is your QFF/VFF/KF status.
Having a lot of points, but low status, puts you down the ladder for upgrades.
Any available seats will go to those with upper status first.
You want to go F, so it would be SQ?
As QF does not have an F cabin on their 787 from PER to LHR.
73,500 points is still quite low, really, some people have hundred of thousands,
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You have to backtrack PER - MEL/SYD to get the 380 F, if that is what you want/mean by F.
On the direct QF direct 787 from PER - LHR, J is the highest cabin available.
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Check the work trip rules, if you are able to upgrade.