Cabin crew received a communication last week that Jetstar is operating the A330 on MEL-OOL-MEL once daily effective Dec 3rd. The flight numbers are JQ440/443 - dep MEL 11:00, arr OOL 12:05, dep OOL 13:05, arr MEL 16:20. So look out for her at the domestic terminal.
Not sure how long they'll be running the 330 on the route, was only given a start date.