Invalid Swift Support - Files don’t match

I just re-wrote an app in Swift 2. I'm trying to upload the app to iTunesConnect (via Xcode 7 GM) for internal testing.

I wrestled with an "Invalid Swift Support" error for awhile (which has other, related questions) ... but now it's changed to something a little different.

The error from Apple now says:

Invalid Swift Support

The files libswiftCoreLocation.dylib, libswiftCoreMedia.dylib, libswiftCoreData.dylib, libswiftAVFoundation.dylib don’t match

/Payload/http://ift.tt/1XTi1Om, /Payload/http://ift.tt/1FBPwcO, /Payload/http://ift.tt/1XTi1Oo, /Payload/http://ift.tt/1FBPyBu

Make sure the files are correct (?), rebuild your app, and resubmit it.

Don’t apply post-processing to

/Payload/http://ift.tt/1XTi1Om, /Payload/http://ift.tt/1FBPwcO, /Payload/http://ift.tt/1XTi1Oo, /Payload/http://ift.tt/1FBPyBu.

I've been unable to find similar errors by searching for "Don’t apply post-processing", "Make sure the files are correct (?), rebuild your app, and resubmit it", etc.

Does anyone know how I can "Make sure the files are correct" --or-- any other recommendations? Thank you.

via Chebli Mohamed