Thanks, that worked for me too. Automatic signing is broken for me. Here is what I did to complete an upload.
On https://developer.apple.com/account/resources/profiles/list
I added a new iOS Development profile and a new AppStore profile. Both these profiles have the specific bundle ID of my app set as app ID. My app has an extension so I needed to create two more (dev and distribution) profiles, with the extension bundle ID. In Xcode Target settings for my app and for my extension I switched off Automatically manage signing in the Signing and capabilities tab. Under Provisioning profile, I selected the development profiles I had previously created. I archived the app and in Organizer began a distribution setting. During the process it asked me for distribution profiles for the app and the extension, and here I selected the second set of profiles created on the developer web site. Clicked OK and it worked....