The source DESCRIPTION for this object is empty, but its name, its UNITS of seconds, its DEFVAL of 0, and its pairing with dialBackupFailoverTime in this table suggest it sets how long the primary interface must stay back up before traffic switches back from the dial-backup connection to the primary link. A network administrator would tune this to avoid flapping back and forth if the primary link is intermittently unstable right after recovering. For example, setting dialBackupFailbackTime to 60 would require the primary interface to remain stable for 60 seconds before the device fails back from the dial connection.