How can Members "expire" after a certain time period?

In the settings for each user, you can set the number of days for which the membership should last. ListManager will automatically "expire" that member once their membership runs out.

For instance, you can set the expire date to "365" to give your members a one year membership to a group.

After a member expires, they are not erased. Their membership settings are kept, but their "status" changes to "expired" and they are no longer able to participate. To reinstate them, you need only change their "status" to "normal". See Utilities: Members: New Member: Settings for more information.