@J-3804, Danny, Thanks for posting in Q&A.
Based on my research, the setting means Number of continuous days with no signal from the partner before Intune considers the partner unresponsive. For unresponsive partners, Intune will consider the connection lost and ignore the threat level/risk score across all devices.
So, if a user is on vacation for 2 weeks, their device will not automatically offboarded from Defender and the status will be unresponsive, but when the user returns and their device starts communicating with Intune again, the status will be updated, and Intune will consider the partner (Microsoft Defender for Endpoint) to be responsive.
Hope it will help.
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