>>Not sure if this is true or if it would even be possible to enforce,...
Here is the US, backhauls from mobile towers are quite separate (both physically and routing wise) . Not sure if that's worldwide practice but if Ukraine is set up like that, it'd be simple-ish to disable mobile data.
Written by Bob Koure
Retired software architect, statistical analyst, hotel mgr, bike racer, distance swimmer. Photographer. Amateur historian. Avid reader. Home cook. Never-FBer