Open Radar

 
Summary:
The iPhone 6+ is locked in mini-setup. Going through the steps leads to a dead end, going backwards results in the phone rebooting, or at least looking like what happens when springboard "reboots", but faster than a full reboot.

Steps to Reproduce:
1. Upgrade iOS 9 OTA
2. Phone Upgrades
3. Unlock on "Hello, swipe to unlock screen"
4. Press "Continue" on "Update Completed" screen.
5. Get "Installing configuration from (null)" screen with a grayed out "Next" button and a blue "<Back" button. 

At this point the phone never moves on, never finishes "installing config". I have waited an hour+ with no changes. Pressing the "<Back" button causes an iCloud sign in screen to appear for a short second, then the phone reboots. This process repeats forever.

Expected Results:
Complete Mini-setup, be able to use my phone.

Actual Results:
Phone unusable. 

Version:
iPhone 6+ upgraded to iOS 9 from the latest version of iOS 8.

Configuration:
This iPhone was once "Supervised" with Apple Configurator and set to auto-enroll in MDM using a URL. It was already enrolled in MDM at the time that the iOS 9 OTA update was initiated.