If it is in Jetstar colours and on their AOC, carrying their passengers (i.e. not a wet lease), then of course.
AIPA couldn't stop it anyway, which airline QF give the aircraft to is their prerogative.
The aim of this push for unity is to prevent each party being played off against each other leading to UNDERCUTTING as has happened in the recent past.
Gee some of you are a bit slow!