App rotates when UIAlertView is shown in iOS 8

I am working on an app that is mostly used in portrait mode (except for a few views). We are encountering an issue in iOS 8 where the app is able to rotate when an UIViewAlert is shown, even though the underlaying view controller only supports portrait orientation and its shouldAutorotate method returns NO. The rotation is not even full as the UIAlertView rotates to landscape, but the underlying view remains in portrait mode. There is no problem if we run the app in iOS 7.

I know that UIAlertView has been deprecated in iOS 8 and that we should now use UIAlertController. However, I would really like to avoid having to replace it as this would mean editing 50+ classes that use UIAlertView and UIAlertViewDelegate. Also, we still support iOS 7 so I would have to have both solutions. I would prefer only to have to do this once, when we make the full switch to iOS 8.