Answer:
Renewal permit applications need to be with the road managers for a minimum of 14 days, and if no response is received by NHVR the permit can be issued (expedited). We suggest submiting your renewal application in plenty of time (at least 16 days before permit expiry), to allow time for the NHVR to send your application to the road managers. If renewing a permit within 14 days of expiry, you may be without a permit until it is issued.
Note that you are able to apply up to six weeks before your permit expires.
If the application is submitted after the expiry date of the permit, the NHVR is unable to expedite the application and it will be treated like a new application.