What triggers the ORA_CHK_TASK_EXPIRED_PERFORMER Alert?

Summary:

With 23B, Oracle made the expiration days a mandatory field. If I have to set an expiry date on all tasks, how do I let the performers/employees know that the task has been expired? I was thinking this alert looks like it should let the performer know but there is no option under Notifications and Reminders to specify that when a task is expired that the performer should be notified. I did a test and my tasks expired but I received no alerts. Right now the employee would only see the tasks in an expired state.