We live in the mountains where we have frequent multi-day power outages that take out the regional Comcast internet service, and where there is no cell coverage. (1) If we install a powerwall + solar, how do we do monitor the state of charge in the powerwall so we can conserve remaining power if it is getting low? I’ve wired a cabin and trailer for solar/battery, so I know how to get a rough estimate of state of charge by knowing initial charge and then tracking powerwall inputs from solar and outputs to our house, but are there better options? (2) Someone on this forum mentioned using an old cell phone to get limited information directly from the gateway (without being able to change settings). Are there instructions for how to do this? (3) If we just want to use in backup mode during a power outage, would we need to communicate to change settings? Or will the powerwall continue to work in backup mode?