When attempting to connect to PlayerIO ( QuickConnect.SimpleConnect() ) from a game running the latest Unity beta (2017.1.0b4), it returns a "NetworkIssue" error.
The same code works without any problems at all in prior versions of Unity, so I suspect this is the result of a change on Unity's end. I know for certain that I had to go through and change all of my WWW error detection, because WWW.error now returns a blank string ("") instead of null on a successful operation.
Figured I'd throw a heads up out there, in case it hadn't already come up. If there's an updated version of the Unity client DLL that is compatible with Unity 2017.1.0, hit me up! <3