Extension of registry documents applies for registry certificate and Ship station license
It is required when owner fails to provide documents required for permanent registry before provisional registry expire or before renewal of permanent registry documents
Required documents for extension are just copy of the expired certificates and power of attorney in some flag states
Some flag states limit extensions of the regisration certs to one year and some to six months after that vessels shall be deleted automatically of permanent documents are not submitted
Please see our flags sections for full details under different flag states