Then barring any sneaky manoeuvre by Qantas they return to a rank and fleet their seniority will get them and go from there (could well be 330 SO if no other positions available), as I think the vast majority will do if it comes to that.
I imagine for most the 3 year LWOP and associated command time (MOU FO's aside) is like insurance. If QF really goes tits up you have more scope to go elsewhere.
Back to topic.