title: How do I upload a build to TestFlight from a beta version of Xcode?
body: <p>I'm using Xcode 8 Beta 4.  When I archive the project and then hit Upload to App Store with the intent to distribute the build through TestFlight, I get an error from Xcode saying:</p>
  
  <p><code>Invalid Toolchain. New apps and app updates must be build with the public (GM) versions of Xcode 6 or later, macOS, and iOS SDK or later. Don't submit apps built with beta software including beta macOS builds</code></p>
  
  <p>I understand that I can't go to the App Store until Xcode 8 GM is released, but is there a way to simply distribute through TestFlight with a not-yet-Gold Master version of Xcode?  The version of the app I'd like to have tested won't build with Xcode 7 because I've migrated to and utilized some new features in Swift 3.0</p>