I had the same issue when launching our app in landscape on an iPhone 6 Plus.
Our fix was to remove landscape supported interface orientations from the plist via project settings:
and implement application:supportedInterfaceOrientationsForWindow: in the app delegate:
- (NSUInteger)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window {
return UIInterfaceOrientationMaskAllButUpsideDown;
}
Apparently the information in your plist is to specify what orientations your app is allowed to launch to.