Originally Posted by Awgd8

firulice, It is a file name back2stock that your tuner will provide you. You need to find out your ECU serial number by calling Infiniti parts dept. and he'll ask for your car's Vin#. He will then give you the ECU serial #

That serial # can be cross reference with the Uprev Matrix. (List of Uprev supported ECU) - If your ECU is on the Uprev Matrix, your tuner can find what file you need to flash your car back to stock. It is like flashing your car with a new tune. Once you flash it back to stock, uprev Cipher will not be able to read your ECU , unless you reflash the car using your latest Etune file.

Yes, you keep that backtostock file like a regular etunes.