I found a couple threads on the issue hence the question.
https://www.ttforum.co.uk/threads/bag-in-coolant-tank-reservoir-bursting.2030154/
https://www.pistonheads.com/gassing/topic.asp?h=0&f=23&t=2056688
Would not put it past Audi to keep doing something daft like this and leave owners to carry the can. If my car has this I will get it removed if it has potential to cause issues, I do not need any more hassle from the S6 POS edition.