I know Virgin Atlantic doesn't fly to Sydney anymore but just in case you have some Flying Club miles left over. They are offering a reduction for point redemptions.
Pretty good deal but you will need to make your own way to Hong Kong, Tokyo, or Shanghai.
60,000 miles from HKG to LHR in Premium Economy is a pretty good deal
If you tag this to a Qantas Syd to HKG special for about $800, this makes it a pretty good deal
Thanks to AusBT for the heads up!