You could complete a cash bid now upgrade.
Or you could simply open a QF account, make a purchase, earn the bonus points which would be enough for an upgrade -
https://wine.qantas.com/p/thorn-clar...19/THCWLRCAB19 - happy to supply an address ;-)
you may also be out of luck as it is BA stock. There have been similar questions in the QF forum on how to upgrade when not QF stock.