I've seen the report you linked to - but that only shows there is a problem. Many nights we are "using" over 1GB of data while we are asleep. This happens even when we are not home. At one stretch we were gone for three days and used almost 6GB of data. How does that happen?
I've shut down all of our devices and changed the PW on the router to ensure there is nothing connected that I am not aware of. What is extra strange is that we are doing nothing different than we were usage wise for the first several months on this new setup. Suddenly last month we started using much, much more data than we were previously.
At this point we have the router shut down - which means our primary home phone number is also shut down. That can't possibly be how this service is supposed to work. At this point I am ready to cancel this service and just keep our cell phones. It is turning into a disaster.