What does tower do to stream video on Android 6.x devices?

Tower connects and stream UDP video just fine on any Android device (with cellular network or not.)
QGC , fails to stream video (but telemetry is ok) when on an Android =>6.0 that has cellular internet access.

Apparently this has something todo with the way 6.x acts, and requires some command to use the wifi, rather than cellular network…

Could somebody point me to the code Tower is using to solve this ?

@Andre-K I’ll try and find some time to look a bit later

Thanks , the closest I’ve found is https://github.com/DroidPlanner/Tower/blob/671730426d00cdf8b1063c879266ea80bd798c3c/Android/src/org/droidplanner/android/AppService.java#L126

also line 146, 158, 163
But I don’t see how missing that affects video only, not telemetry. - So I am not sure it’s all.