You know, even if you have a fallback internet connection in the form of a 5G router that is very well capable of lifting all the data processing via mobile if necessary, all things fall apart if the main router ends up in some kind of weird loophole where it'd switch to the fallback connection once every... few hours and then return to the main connection, which might or might not have failed, I don't know, because when I returned a week later and rebooted everything worked just fine.