After few days of testing and digging i found nothing wrong with WireGuard... it turned out that for some reason after using WireGuard, WiFi Calling and/or VoLTE started to go crazy and eat up battery.
After disabling both features and with WG in Damand mode (always on) and 8h battery dropped shocking 2% ...

now, you/I can dismiss that report or try to find why Wi-Fi Calling and VoLTE going crazy with wireguard enabled. It might be bug in iOS, bug in T-Mobile implementation, bug in CFNetwork, or vpn extension, who knows. If you have ideas about that let me know.

thanks all for listening.
__
kolargol

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‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Thursday, February 28, 2019 1:07 PM, kolargol <kolargol@protonmail.com> wrote:

> Hi
>
> Thanks for great work with Wireguard, it's fresh breeze of air compared on years spend on OpenVPN...
>
> I am testing WG on varius OSes and devices and I have noted severe battery drain on iOS (12.2, iPhone 8). Typically battery drops 40% during night-time (that is 7 hours of inactivity on the phone) when WireGuard is engaged.
> Is this some kind of known issue? I did not had chance to test previous iOS version without SIMD ChaCha20 support so i cannot tell if it is becouse of the last update.
>
> Anything i can do to track issue here?
>
> thanks,
> kolargol