It seems pretty obvious, that in order to qualify for any of these insurances is that you must have a defined 'trip' as in return flights back to Australia. The cover is meant to be for holidays, not for australians residing overseas.
If it seems ambigiuous, dont worry about that and just make sure you have a return ticket before you leave.
If it seems ambigiuous, dont worry about that and just make sure you have a return ticket before you leave.