@OllieSaleh Thanks for posting in our Q&A.
For this issue, we appreciate your help to get the setting of App availability. Basically, there are two settings for the app installation time, App availability and App installation deadline.
I also find that when more than one assignment is made for the same user or device, the app installation deadline time is picked based on the earliest time possible. We can read the following article as a reference.
https://video2.skills-academy.com/en-us/mem/intune/apps/apps-win32-app-management#set-win32-app-availability-and-notifications
If there is anything update, feel free to let us know.
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