Retain Unified Archiving 4.9.1
In the Retain Admin Console | Overview | Reporting | Manage Scheduled Reports | a scheduled report is modified and the start date remains in the past, the report will be deleted after the changes are saved.
A small box will appear in the upper right corner for a few seconds stating: The selected start time has already passed.
This has been reported to engineering as a defect.
The current work around is to modify the Start Date to the current day or a day in the near future before saving the report modifications.