That's a good question. One of the few procedures Tesla doesn't publicize in the service manual (you need toolbox with security access to see the full steps). My gut feeling is they'd have a mechanism of transferring the config. But then does make you wonder what happens for cars where the computer fails altogether.Do these changes survive computer swaps or upgrades? I'm going ahead with the 'steam' computer upgrade for my car and wondering if I will lose my matrix headlight and other config changes. I have been assuming (hoping) that these config changes are written to Tesla databases and not just the computer in the car.
There are enough procedures that change the gateway that I suspect they might actually be backed up to the servers. But that's a guess