Several things here, as others have posted already you are entitled to a full refund. Scoot cannot put a deadline on obeying Australian consumer law, others have posted that according to the details you have described you are entitled to a refund, are there other pertinent facts that I am not aware of? What steps have you taken (other than talking on the phone to Scoot) to get a refund? I assume that you didn't pay by credit card or its too late for your credit card provider to dispute the transaction? Have you got something in writing, recorded or email saying you are
not entitled to a refund? If so - its off to your State Dept of Fair Trading/Consumer Affairs with that evidence in hand, that is what they will need to take action. i.e. you will need to provide evidence that you have tried and failed to get a refund from Scoot, by refusing to email them you are making that proof harder to obtain. I assume you have evidence of unanswered emails from yourself asking for a refund?
Please do keep us informed - good to hear you were able to book alternative QF flights. Thanks for getting back to us and please let us know how this is eventually sorted out.