How do certificate links work?
In short: Each pack-fresh certificate pairs the documentation sheet for a card with a link to an unlisted copy of the break recording. The shop sells the certificate with the card, and the buyer uses the link to watch the pull.
The link points to an unlisted copy of the recording, so it is not searchable or public on a channel; only people with the certificate can reach it.
The link works for as long as the recording is kept: seven years from the date of the break, unless the client asks for earlier deletion and no dispute is open. When the recording is deleted, the link stops working. See can I ask you to delete my records? and the retention and consent policy.