So, our XC40 Volvo EV's app out of the blue announced that the car had gone off-line and it couldn't communicate with it. Nothing in the manual to tell me how to go back on-line, so I go to Volvo's help chat. Long story short, it seems that after a software update you need to re-start the mobile radio modem by pressing the 'defrosting' button - to the right of the red emergency triangle button - and looking at the same time at the SOS button overhead to see if its LED starts blinking. If it does, the car is back on-line - or will be after a re-boot... lovely user interface 🤪