So I left the car in parking mode and a mobile tyre fitting company came and changed all four tyres. The device did come out of parking mode because I got audio, so I guess it thought it was moving, that's fine. Car was jacked up, bloke took the wheels off with a pneumatic wrench, changed the tyres, put the new ones back on and tightened with the wrench again and lowered the car. Then used a hand wrench to get the right torque on the bolts. To my surprise, the G-sensor didn't record an event once. It was set to maximum sensitivity.