iPhone Duo: Keep app on inner display while hinge is open (like Clock)?

Hi!

I'm building a night-light app for iPhone Duo. When the device is partly open in tent mode, the lamp starts on the inner display. As soon as I set the phone down on a table, the system moves my window to the outer display, even though the hinge stays open.

Apple's Clock app stays on the inner display in the same pose, so it seems possible at the system level.

Steps

1. Open iPhone Duo to ~80° (tent).
2. Launch the app on the inner display.
3. Set the device down on a table.

Observed (logged from the app)

• UIHinge.status stays .partiallyOpen (~80°), not .closed.
• UIDevice.orientation goes portraitUpsideDown → faceDown → landscapeRight.
• UIScreen.didDisconnectNotification fires and UIScreen.screens drops the inner screen.
• The window moves to the outer screen (466×678).

What I've tried

• Restricting UISupportedInterfaceOrientations to portrait only
• Turning on Rotation Lock
• Reading UIHingeInteraction (read-only, no effect on display routing)
• Looking at UISceneAccessory.cameraCapture, which only applies with an active capture session and a fully open device

Question
Is there a supported way for a scene to prefer or stay on the inner display while the hinge isn't closed? If not, I'll file a Feedback Assistant request.

iPhone Duo · iOS 27.2 · Xcode 27.2