Symantec Data Loss Prevention (DLP) Enforce
In the Enforce console go to "System > Incident Deleter > Delete Incidents".
Open the "Next scheduled deletion time" window.
Select "No Regular Schedule".
After the Enforce services are recycled or the server is rebooted, the schedule defaults to the daily schedule.
Working as designed.
An Enhancement Request (ER) has been submitted to Product Management to change this functionality.
There is no guaranty that this ER will be added to the product.