dataTaskWithRequest returning empty responseObject on 200s (ios 8.3 builds on ios 9 only)

Question

This is not a duplicate of NSURLSession/NSURLConnection HTTP load failed on iOS 9

Things I know or confirmed:

• Using default nsurlsession configuration
• Callback reached with error == nil
• [response allResponseHeaders] looks healthy and status code 200
• Not an ATS ios 9.0 problem. Proper https, and http 200 status code
• Confirmed request/response is normal using curl
• ONLY happens on a ios 8.3 build, targeting 7.1, and running on a 9.0 device (all devices running prior versions of ios are fine)

Update: This has now been fixed with ios9 Beta2

Answer 1

This has now been fixed with ios9 Beta2.