VoIP call without internet in iOS 10

We developed iOS app which communicate SIP server.

And it works without access to Internet.

In a thread,Apple staff said, "In iOS 10, you should be using PushKit for handling push notifications for incoming VoIP calls".

PushKit requires internet.

However some of our customers use our app without internet.

What is the alternative way without access to Internet?

Replies

I have this problem too,

so anyone, if there is an answer to it please give one...

There is no alternative way...

The current workaround is to build against iOS 9 SDK with Xcode 7

iOS 9.3.3