I’d put it into the CEO office in Milton Keynes (I think that’s where it is) using soft words involving disappointment with the brand, disillusion that will stop you buying you next Audi this year etc. Needs elevation now (forgive me if you have done this, Ive skim read). I did this when I was getting crap service from Audi dealers and got all my issues addressed on my R8 few years back.