Hi Richard all modern diesels have dpfs now I'm afraid. If the car doesn't do long runs then the dpf can clog and worst case scenario it'll have to be replaced which will cost around £1000+
Cheers
Steve
Welcome to the forum Warren, you'll find the members on here are a friendly and helpful bunch 🙂
sorry to hear of your issue, my a6 also got hit from behind in 2017 but was also rebuilt.
cheers
Steve