Ok.. Clear things up abit.. If the Ford dealership is "Smart". They can work out if ANY ford, BA to FG has been tuned.. Say.. I've got a BA falcon.. The initial factory catch code is A3HA.. I then get my car tuned. Flash box reads A3HA out of the pcm, and stores it in the "F" position, allowing me to flash it back at any chance to fool ford dealerships... I take my car to service, Flash Factory tune back in. Ford Service my car. Ohh there's a PCM update.. They apply A3HD to my car.. I pickup my car, Drive around the corner, and flash my custom tune back in. Now..... Think what just happened.. The flash box flashes the custom tune back in. It doesnt care what was in it before it overwrote the tune, it only cares if the VIN number is the same. Come next time I take my car to get a service, When I flash the tune back in, Im flashing A3HA back in... Ford plug into the car.. Oh there's a PCM update available.... "Checks records" hang on a minute, this car according to our records should already have A3HD Ford's IDS software does not allow you to backward downgrade a PCM. Its designed very foolproof so any bush mechanic can operate it. Now, with BF and FG.. They got ingenious with the PCM. And embedded a "Flash Counter" which increments everytime you flash your vehicle. A usual vehicle will only be flashed upto 5 times in its life, maybe 10 times maximum if only ford were applying updates...... If you custom tuned your car, I garentee there will be AT LEAST 10 flashes to setup that one tune.