Qantas will order a big amount of 787-9's. Some will go to Jetstar, the majority will go to mainline along with some 787-8's that will return from Jetstar once the 9's are online. I could see the 737's being replaced with A319/20/21 as the Qantas group already has loads of these on order and the Jetstar franchise experiment has failed so they don't need many more apart from replacing some older frames.