Scirocco Central

There is a company in Luton which is advertising this service.

It's really interesting that it is possible. Presumably the software and passwords for doing it must have escaped into the wild at some point.

It may also open up a route for loading remapped firmware, which AIUI was previously not possible and the only way was to insert a signal-faking box between the engine and the ECU.

Hello, that is wrong, I already had my car remaped after fix and everything is great. Also did DPF Delete.
Reversing update from VW is possible if you did a backup before. After that, original map is gone with VW update.

How would you do a backup, and where is the backup stored?

I thought these ECUs were encrypted.

Could you please post an explanation with more details? Many thanks.

I have the VAG-COM cable and software, bought on Ebay a few years ago. It's handy for stuff like unlocking both doors concurrently, beeps on unlock, etc. But many of the data fields are blanked out because the software developers didn't have access to the full documentation.