I assume that this is because you want more status credits, correct? If so, you can claim original routing credits even despite flying directly - including DSC. It's not automatic, you will need to initiate yourself, but it's possible. So to be clear, you can now fly direct, but claim the original credits including double status for DRW-MEL-ADL, without the hassle of actually doing that routing.
If you're rebooked on a different flight, request an "original routing credit" to get the Qantas points and status credits you should have earned.
www.australianfrequentflyer.com.au
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You can apply for an Original Routing Credit if you are involuntarily re-routed or rebooked on another airline due to a flight disruption. This could be needed if the new itinerary would leave you with fewer points and status credits than you would have otherwise earned.
For example, you might have booked a Qantas flight from Canberra to Perth via Melbourne – but the flight to Melbourne was delayed, so you were re-booked via Adelaide instead. The new routing would earn fewer Qantas points and status credits than what you had originally booked. So, you could claim for the difference.
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