What happens if my domain registrar goes out of business?

Your domain does not disappear. Registries have processes for this, but the transition is smoother if you are prepared:

• The registry holds the authoritative record - for .au that is auDA’s registry, not your registrar.
• Registrations are usually bulk-transferred to another accredited registrar.
• Your contact details are what protect you - if the registrant email is stale you may not be told, and may not be able to prove control.

Check your registrant contact details are current and are addresses you control. That is the whole preparation.