Example: Frank Kern (marketer) says in an email "you have an hour to get his XYZ)" and when the hour passes, it triggers that the link in the email reroutes the person to “offer no longer available”... (an expiring link)

When I saw this, he used InfusionSoft (now KEAP).

Inside of Kartra, they have links that can send people according to a tag.

When clicked, does contact have "XYZ" tag?

If Yes, send them to URL1.
If No, send them to URL2.

Inside of Kartra tags can be set to expire (individually for each user), from when it was set. When it expires it is removed.

Example:

New Tag Created called: 2Weeks (expires 14 days : 0 hours : 0 minutes)

Flow Example: User1 enters sequence on December 1 and given tag "2Weeks". (That tag will expire and be removed from that user on December 15.)

Flow Example: User2 enters sequence on December 3 and given tag "2Weeks". (That tag will expire and be removed from that user on December 17.)