Qantas has introduced DRW-PER-DRW flights three days per week and similar timings. I noticed it last week in the QF schedules so perhaps QF had a 'heads up' on DJ's plans.
In addition to the DRW-PER flights are three extra DRW-ADL flights. All ops by -800s.
I am sure Jetstar would have done OK connecting their two new hubs for SE Asia flying (DRW-PER). It would be harder with DJ already on the scene. Although JQ had no worries pushing DJ and Tiger off the scene with their recent ramp up of DRW - so not unheard of.