The Expired Date field indicates the time and date that an Accounts password became expired.
For example, if you have an Account set to automatic reset when a Check fails due to mismatch, then the Expiration Date would be the time and date of the mismatch test.
This can also occur for Manual Accounts. The Expiration Date would be the date on which the Manual Account sends the notification that it needs to be reset.
This field will be blank if an Accounts password is not expired, or if it is reset immediately after becoming expired. So typically, you will only see a value in this field if the Account is outstanding and has not be reset after becoming expired (due to the Change Agent being disabled or the System not being reachable etc)