A user's access to a site is disabled after a specified number of days. The admin can set the number of days since registration to deny access.
Expires a user's access to a site after a specified number of days. It uses the user registered date/time and an admin configured number of days to determine when to expire the users access. The administrator can restore a user's access from the user's profile page.
There is a filter available for developers to hook into and alter the expiration date of a specific user on the fly during authentication. The filter uae_expiration_date passes the current expiration date and the WP_User object.