I can assure you that JQ flights MEL/SYD are not full, I have been on 2 flights last weekend with no more than 25% of the seats taken, including an A321.
From what I can see ZL is adjusting the schedule on MEL/SYD to 5x daily MON-THU, 7x on FRI, 3x on SAT and 6x on SAT. A slight reduction in...