Kanga1,
I was told that the original two aircrafts rego's were chosen and painted onto the new aircraft without having been registed first with CASA, Jetstar had already reserved the rego's VAus wanted, and the aircraft had to be re-painted with the correct rego's, if this is the case, it does not surprise me.
A little birdy also told me that for some of the pilots that have left good job's oversea's, their right to return to their previous employer is approaching it's deadline.