Under the current arrangement, the A330s owned and operated by mainline are transferred to Jetstar, and then returned to mainline when the 787s arrive. So in effect, the costs of transferring these aircraft (repainting, reconfiguring etc) are paid twice.
I didn't think they weren't planning on doing much reconfiguring since the J* international and mainline domestic were meant to be equivalent. Seems different now with change of mind on domestic business class.
Also, management have repeatedly stated that they will allocate capital within the group wherever they can get the best return. So I wouldn't have thought that being capital constrained was a factor.
The lack of dividend suggests that the group as a whole is capital constrained.