Owners and registered agents of Australian registered ships are required to comply with the relevant laws and regulations.
You have these obligations if you own a vessel.
If you do not comply with the above obligations, you can be fined. The maximum penalty for the most serious offence is A$20,000, two years imprisonment, or both.
Links
[1] https://www.amsa.gov.au/vessels-operators/ship-registration/transferring-ownership-australian-general-register-vessel
[2] https://www.amsa.gov.au/forms/notice-change-name-caveator-or-change-address-service
[3] https://www.amsa.gov.au/vessels-operators/domestic-commercial-vessels/domestic-commercial-vessel-requirements