737/330?
If its the 330 you in the end getting, its a wowish factor, having a sash seat belt, ie, not straight across waist, but from left or right shoulder to waist.
I did my first J 330 about 2 years ago with QF on the 330, had to phone up 3 times to change my flight, as they kept chaning the plane from a 330 to a 737 for the times I had booked, each time after I rang, the plane changed again to a 737.
In the end, after the third ring, I got my dream of the J 330.
Get to MEL T1 about 3 hours before flight, its domstic, so you can do OLCI, print your BP, get through domestic security premium screening, get to the J lounge, due to the fact that you have a J BP, you won't need to have any lounge visit pass scanned, as your BP will suffice.
Go through the double glass doors that says, QF lounges, T1 MEL domestic, go up escalators, turn left, have your BP ready for scanning, no photo id needed, just BP.
Have a meal/snack, grog if after 12noon, save some time for the food on the plane.
Grog in the QF side only gets served after 12noon on the dot, no earlier.
Then 45mins before flight, go to gate, so you do a DYKWIA, stand in the premium queue, dare the others in Y to join you by looking at the long queue in Y, have your BP scanned as you will be first on, if 737, they might join the queue, if its 330, J will have a separate gate.
Store your HLO up in the overhead bin, sit in your seat, if 737, let the masses be envious of you, if 330, you will not be seeing anyone in Y.
If after 12noon flight, you can ask for "free" alcohol, sometimes they might offer you a sparkling water or orange juice, for pre take off drink, but it won't be the very expensive stuff to drink, ...
About 15/20min, after, they will ask you what you want for your main meal, if lunch, you will have a choice, half an hour into flight, they will start to serve, and then an hour into flight, they will do pack up of meal trays...
Last 30mins, a bit before on descent, you will have to have the tray table cleared, and then secured for descend and landing.
In the end, its very short flight.
If you really want to feel QF international, going on the 330 to NZ wouldn't be too expensive, can go on a J one way MEL/SYD/BNE to AKL/CHC/WLG, can come back in Y.
Enjoy the flight.