[Completed with warning]: The site database has a backlog of SQL change tracking data.
Check the auto cleanup status:
SELECT * FROM sys.change_tracking_databases WHERE database_id=DB_ID('<database_name>')
Review this doc for more detail steps: Troubleshoot change tracking auto cleanup issues.
Besides, see if this article helps: SCCM-The site database has a backlog of SQL change tracking data.
Best regards,
Cosmog
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