Points about to expire but no time for holidays?? Book the round Aust trip (or other preferred trip) on the day before your points expire and make the start date of the FIRST leg of your journey one year in advance (I’m not sure if the entire journey must be COMPLETED or STARTED within 12 months). Anyway at least your points get deducted immediately (no lost points) AND you effectively get 1 years extension them. Also, (with Qantas at least) you can change the dates of flights as much as you like with no penalty as long as you do not change your itinerary.
** Some overseas frequent flyer programs allow you to “donate” points to a worthy cause (eg. the Red Cross to be used to fly needy patients to major cities so that they can have life-saving medical treatment).