Requirements for App Store
To take advantage of the new features provided by the iOS 11 SDK, Apple will require that all new apps submitted to the App Store must be built with the iOS 11 SDK. This requirement takes effect starting April 2018.
This means that to submit any new apps, you will have to use Xcode 9, which provides the tools to build apps for the latest SDKs, including iOS 11, tvOS 11 and Swift 4.
For details, see the Submitting iOS apps to the App Store documentation.
Native SDK support
Following Apple’s lead, the Brightcove Native Player SDK for iOS/tvOS v6.3.5+ no longer supports building with Xcode 8. If you have not already done so, please migrate to Xcode 9 as soon as possible.