Even the unchanged (except the coordinates) example project from the WWDC works unreliable. Exactly same behavior as in my app. I think we have to wait here for a future iOS update...

Addition: I implemented a one time location update via CLLocationUpdate for testing purposes when the user resumes my App from background to force the system to calculate a high accuracy location. This "workaround" indeed helped to accelerate triggering other apps which are monitoring similar geofences, but not my specific CLMonitor instance, which remains stuck. As I mentioned already, killing and relaunching the app helps to trigger an entry event. The events date is the time of relaunching the app and not the entry time. I am making a few REST calls inside the monitors event loop, which should only require less than one second under good conditions. Also the testing geofence is located in an area with a lot of Wifi APs. Other Geofencing Apps which may use the old API are just working as expected.

iOS 15.3: same problem.

Same issue with pure APNS (without FCM) iOS 15.2, iPhone 13 Pro Max After a few hours the delivery is not working anymore because of the same policy. Even if the app is running in the foreground (with or without attached debugger), no background notifications are delivered. A reboot of the device helps temporary for a few hours