I have added Default-568h@2x.png to my project and set it in project settings, I have also set autoresizing options for my view and element
How are you adding the main viewController to the window? Just adding the view as a subview isn't supported any more in iOS6.
Here's an except from an article on my blog about making apps work on the iPhone 5 screen size.
Use window.rootViewController to add your initial view
First up, if you're building your initial views in code make sure you add your initial view to the window with window.rootViewController rather than the old way of simply adding the view as a subview. If you don't do this, autorotating will not work at all for your app under iOS 6.
Here's an example:
navigationController = [[UINavigationController alloc] initWithRootViewController: myRootVC];
//[window addSubview:[navigationController view]]; Don't do this!
window.rootViewController = navigationController; // Do this instead!
More at http://pervasivecode.blogspot.co.uk/2012/09/making-apps-work-on-iphone-5-screen-size.html