If your registration has expired, it is illegal to drive your vehicle until you have paid your registration fee. If the fee is not paid until after the expiry date of the previous registration term, the registration status of the vehicle will be ‘expired’, meaning the vehicle is unregistered and possibly uninsured, until the fee is paid.
The expiry date does not change if you pay late. If you drive an unregistered vehicle you can be fined.
You can only renew your registration up to 3 months after the expiry date. After this date, you will need to apply for a new registration.