Hi,
Maintenance window that is applied at collection level is for the device and any deployments that are targeted to the device will happen during the maintenance window.
In your case, yes, the client that is part of any collection will have the maintenance window of 1am to 5am.
For more information about the maintenance window, please read https://video2.skills-academy.com/en-us/mem/configmgr/core/clients/manage/collections/use-maintenance-windows
Regards,
Eswar
www.eskonr.com
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