The app's Info.plist can't contain values for the UIRequiredDeviceCapabilities key
I removed <string>armv7</string> from the array in UIRequiredDeviceCapabilities in info.plist and now my status is waiting for review. Seems like it was a iTunes Connect-bug in my case
When updating an app, it seems you cannot add new restrictions to the Required Device Capabilities. The automatic validation service that Apple has integrated into Xcode will reject any update with more restrictive UIRequiredDeviceCapabilities than the earlier version before you can even upload it to iTunes Connect.
http://oleb.net/blog/2011/12/uirequireddevicecapabilities-cannot-be-changed-in-app-updates/
I didn't need any hardware checking with my similar issue but removing UIRequiredDeviceCapabilities completely and changing the project format to 6.3 compatible seemed to get around this issue for me.
Mine was an old project, originally set to Xcode 3.2 compatible.