iOS 27: Opening Notification Center triggers didEnterBackground instead of remaining inactive

Has anyone else observed an app entering the background when the user simply opens Notification Center on iOS 27?

In our app, fully pulling down Notification Center triggers both UIScene.didEnterBackgroundNotification and UIApplication.didEnterBackgroundNotification. The user has not pressed the side button, gone to the Home Screen, or switched to another app. In the iOS 26 environments we checked, opening Notification Center only made the app inactive.

User-visible impact and recording

Our app currently treats background entry during an active medication reminder as leaving that reminder session: it closes the reminder screen and schedules a follow-up. As a result, merely checking Notification Center now triggers that existing behavior.

Screen recording: https://drive.google.com/file/d/1KmXEKwg1vJpCWqe56IrC_iHaEC2aH_fc/view?usp=sharing

The recording shows Notification Center being opened from the reminder screen, including a return to the app's main screen instead of the reminder screen. It also includes opening and dismissing Control Center, as well as going to the Home Screen and returning to the app. These are separate interactions, not one continuous Notification Center interaction. The video illustrates the visible impact; the lifecycle evidence below comes from separate logging.

Environment and observations

• Physical device with the issue: iPhone 14 Pro, iOS 27.0 release build 24A435. We also observed it on an iOS 27 developer beta.
• Devices without the issue: iPhone 11 Pro running iOS 26.5.2 and iPhone 16 Pro running iOS 26.6. Opening Notification Center did not trigger background entry on either device.
• These comparisons involve different devices; we have not isolated the OS version as the only variable.
• App lifecycle: SwiftUI App + WindowGroup + @UIApplicationDelegateAdaptor. Multiple-scene support is disabled.
• The app uses AlarmKit for medication reminders.

Verified build environments (simulator reproduction)

All three groups reproduced background entry when fully opening Notification Center on the iOS 27.0 simulator (24A434). The same SDK 26.4-built minimal apps remained inactive, without entering the background, on the iOS 26.4.1 simulator (23E254a). The behavior therefore also reproduces with apps built against the older SDK, not only with the iOS 27 SDK.

Steps to reproduce in our app

1. Open the app and leave it in the foreground.
2. Swipe down from the top-left edge to fully open Notification Center.
3. Do not tap a notification, lock the device, or switch apps.
4. Observe the lifecycle notifications, then dismiss Notification Center to return to the app.

On the affected iOS 27 device, the behavior differs between these actions:

Lifecycle evidence

This is a representative trace from earlier instrumented runs, separate from the screen recording above. Times are relative to the first event:

+0.000s  scene.willDeactivate
+0.002s  app.willResignActive
+0.778s  scene.didEnterBackground
+0.780s  app.didEnterBackground

In subsequent instrumented runs on the iOS 27 release build, we also observed UIScene.activationState == .background after opening Notification Center.

Our application's background handler is connected to the UIKit notification, rather than an onChange handler for SwiftUI's scenePhase:

.onReceive(
    NotificationCenter.default.publisher(
        for: UIApplication.didEnterBackgroundNotification
    )
) { _ in
    delegate.handleBackgroundEntry()
}

Separately, a diagnostic observer uses NotificationCenter.default.addObserver to record the UIKit application and scene notifications. The background events are therefore not inferred solely from our own session state or from the reminder screen disappearing.

Questions

1. Has anyone reproduced this on iOS 27? Reports of either reproduction or non-reproduction, including device model and OS build, would be helpful.
2. Is background entry when fully opening Notification Center expected on iOS 27, or could this be a regression or an interaction with our app configuration?
3. Is there a supported API or documented lifecycle distinction between opening Notification Center and actually leaving the app for the Home Screen or another app?

Our standalone simulator comparisons reproduced the behavior with both SwiftUI and UIKit scene-based app lifecycles, including direct sceneDidEnterBackground callbacks.

For context, this earlier Apple staff response describes Notification Center as making an app foreground-inactive. I also found this iOS 27 AVPlayer report about playback stopping after Notification Center is fully opened, but I do not know whether it has the same underlying cause.

Any clarification from Apple or observations from other developers would be appreciated.