Hi, @Ronald Seow
Thank you for posting in Microsoft Q&A forum.
However, for Domain Y, since the last upload of catalogs and updates, it is not identifying itself as requiring those updates when queried in SQL and the number that requires those updates confirmed my findings.
Does it normal before?
The updates can not be identified as required, there may be some problems with the scan, you may check the WuaHandler.log on the client to see if there any error.
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