Russ told us that once you register, you'll be in the system, at least in the last ten years or so. Check their website as to how to get back into the system. Depending on how long ago, you may want to make an appointment to go in to take new photos. They've just recently started taking appointments rather than just go and get in line. Hope this helps to answer your question.
I believe you only need to register once and you'll be in their system still. You should check out the calendar page on their website to find the dates titled "updates". Go to one of the updates and renew anything that needs to be updated (pictures, address, measurements, etc). Hope that helps!
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