@DS
Thank you for posting in Microsoft Q&A forum.
For your example:
Clients will download the policies and download the content at 1AM Saturday(available time).
And the content download happens only when the deployment reaches/passes the deadline date(1AM Saturday-1:30AM Saturday).
For application deployment, after the deployment to collection with available time as current time and deadline time as future time, it took random time of 3-4 hours for the application to display in software center and also download happen automatically. Half an hour later, the content that has not been downloaded will not continue to download.
So content should not download between Deployment Deadline and Maintenance Window, it's recommend to lengthen the time from available time to deadline time.
For more details, you may refer to this article:
http://eskonr.com/2017/08/sccm-configmgr-available-and-required-deployment-options-for-content-download/
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