After upgrading from iOS 10.1 to 10.1.1 the VPN icon disappeared from top status bar (in the vicinity of wifi icon) while the VPN is connected using 3rd-party VPN applications.
… while the VPN is connected using 3rd-party VPN applications.
Given that none of your code is involved here, I recommend that you file a bug report about this. Please post your bug number, just for the record.
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Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware
let myEmail = "eskimo" + "1" + "@apple.com"