aleksandrP Hi. The best way to do this today is to target a Device Configuration policy to postpone new iOS updates for 50+ days and deploy a Software Update policy to the device once you would like the device to update. After the policy is deployed, the device will receive a command the next time it checks in with the Intune service as long as that time window is not selected to be prevented in the Software Update policy. The Software Update policy will override the Device Configuration policy, so no changes to that policy on day 50 are required.
Regarding the second question, after 8pm, upon the next check in to the service, the service will determine if the current time is outside of the times to prevent update installations. If so, it will push a command to update the OS to the device. Because check-ins only happen every few hours, we recommend keeping a 12+ hour time frame that updates are not restricted in the policy. The Software Update policy overrides the Delay visibility of software updates setting, so that you can push updates at a time that is appropriate for your organization. I hope this helps! Thank you.
teh_pianist Hi, thank you! There is no device restriction to force automatic updates. If there is an update available, it will be pushed down to the device naturally after the days set for the delayed visibility of software updates run out. Pushing down a software update policy overrides the device restriction for delaying the visibility of the updates, so if you configure a software updates policy during the 30 days you want to delay the visibility of updates, the devices will update when they sync. Forced software updates install (if available) when the device syncs with the Company Portal. Please let me know if there is anything else.