We have been testing our apps with the iOS 10.0 beta and the apps don't opt-in for messages. The channel preferences update but the user does not receive notifications because they aren't opted in. The same code works for iOS 9 and the apps opt-in and therefore, received notifications. I have checked all the provisioning profiles and they have push enabled so we don't believe this is the error.
Are there any known issues with iOS 10 or will these only be addressed when the public beta is released?