IANAL. It seems like it should probably be covered anyway, without the notification. Assumed consent would cover updates and improvements. No-one is consenting to their car being crippled, surely.
It gets me wondering how well Teslas will function with zero connectivity w/ Tesla. I mean, if the company goes under or (more likely) they drop support for older models, do older cars get bricked and disabled like clients for a multiplayer game that's gone offline?
I doubt they'll completely brick (the car can reboot itself mid-drive while still having throttle/brakes/steering) but I could see most/all infotainment features ceasing to function.