Background shield application reliability

Hello! I am working on a screentime app and wondering if anyone has had success achieving reliable background shield application while using com.apple.ManagedSettingsUI.shield-configuration-service?

I recently switched from com.apple.deviceactivity.shield-configuration (which worked reliably but isn't accepted by TestFlight) and have not found any consistency getting shields to apply while the app is backgrounded.

I believe this is a known limitation of ManagedSettingsUI and want to know if there are successful workarounds or any specific patterns/timing that improve consistency?

Background shield application reliability
 
 
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