So we are currently use PushSharp to delivery push notifications to our apps but recently it seems the Dev sandbox isn't working. Currently we are getting the zero bytes response which means the remote server closed to connection. Yet when we point the code to production it works just fine. I tried creating a new Sandbox APN cert and imported the private key but it still isn't working. I'm not sure if its because of the new APN API, which was mandatory after March 29th, but I would think Production would stop working as well. I did also download and install the new AAA cert.
Anyone one have any idea whats the issue or have the same experience. I'm unsure whether this will happen to Prod soon.