Please be more clear with your question since you are mixing Mac and iPhone questions in the same post about a screentime issue on Mac.

For the Mac question: Can you elaborate on what Tech Lockdown feature this effects? The only scheduling feature for mac we provide is through the DNS Content Policy, which is independent of screen time. If you are trying to enforce app time limits that you set through screen time, the only related feature we provide is in the Config Generator > Mac config > General tab, you can hide the screen time panel in settings with "

Allow Access to Screen Time in System Settings." But I don't think that would prevent screen time dialogs from being interacted with.

For the iPhone question: do you mean prevent installing or uninstalling apps on a schedule?