Apple rejected the first submission of the app with these reasons:
We discovered one or more bugs in your app when reviewed on iPhone running iOS 11.0.3 on Wi-Fi connected to an IPv6 network.
Specifically, the splash screen displays indefinitely on launch.
I've created a TestFlight of the same build and downloaded the app on an iPhone with the same os (iOS 11.0.3). Everything works properly.
How to resolve?