@Yaco-7602,Thanks for posting in Q&A
From your description, I know that you want to know how does Intune judge value of "Signature update overdue".
Based on my research, I found that there is a delay in reporting in Intune. Even if you update the device up to date, it will take some time to get the latest report, or you can also generate an Antivirus agent status report to see the status of the device. Location: Report > Microsoft Defender Antivirus > Reports
Hope this can be helpful.
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