I am planning to go to Bali with my FF points. I live in Melb and don't have enough points (points and pay) to do MEL-DPS return. I do have enough to do ADL-DPS return however. I could spend $40 on a cheap MEL-ADL flight then use pay and points for the Bali flights. Interestingly, the flight back comes via MEL. There is a number of hours layover and I imagine we clear customs here at MEL. If that is the case, can I then just make a late notice cancellation of the final (now domestic) leg from MEL to ADL. I do realise that I wouldn't get any refund or anything, but nor would I have to buy another $40 ticket to get back to MEL from ADL.