Originally Posted by
LHR/MEL/Europe FF
You will be fine.
After you collect your cabin bag (arrivals, landside) you can head back into the DOM terminal (clear security first) and then over to the transfer bus point for the ride
QF is also offering a Gate Check service or "Premium Hand Luggage" for the Dash 8's. Just get the tag from the gate agent, attach it to the bag, leave the bag at the steps onto the aircraft and collect the bag when you step off. No need to go landside at all.