someone suggested that if you have a remap and take it to audi and there is an engine/electronic fault etc they will by default just reset everything including your remap, taking it back to the original settings.
It will require a greater expert than me to answer that properly, but I'm pretty sure it's exceedingly unlikely to happen (unless the actual hardware containing the eprom is replaced), and if it did happen Stealth would do the remap again for you.