Email a formal complaint, CC (not BCC) to state consumer affairs
You can use the following templates:
Keep all receipts for your expenses, and itemise your costs in the complaint email. Mention that you have all your costs documented, and ask them to “make you whole” for your losses. Mention that if they don’t compensate you within a “reasonable”, named time frame or indicate that they have escalated your complaint to be addressed by a particular date, then you will request that consumer affairs pursue a remedy.
Any reply you receive that mentions terms and conditions of your ticket, that’s the crux of the matter. Bear in mind that consumer law in Australia overrides terms and conditions; or at least it’s supposed to. We have to kick up enough of a stink that regulators start to step in and make the airlines cease their BS.
The squeaky wheel gets the grease.