Because Apple requires you to support the new iPad multitasking layout, it seems an app would need to function in both landscape and portrait. If I lock every UI to portait, will Apple view this as a reason to reject the build?
Will Apple reject a TestFlight build with all UIs locked to portrait?
Apple does not require you to support multitasking as far as I know. If you DO support multitasking, however, that means you must support all orientations. But if you opt out of multitasking by adding the UIRequiresFullScreen plist key, then I believe you can still restrict orientations.