If you are holding a tourist visa and cannot depart Australia as planned. You must ensure you remain in Australia lawfully. Under the current law, a tourist visa or ETA is unable to extend the period of stay, however, you may apply for a new visa before your current visa is expired. Before you make application for a new tourist visa or ETA, the “no further stay” condition is not applied to your current visa.
If you hold a visa with the “no further stay” condition and is unable to depart Australia as planned, you may make an application to request to waive this condition if your visa will expire in less than four weeks. If your request is approved, you may apply for a new visa before your current visa is expired.