I agree with the above and probably change it at the 8 year point - why, just because I feel that that might be a useful thing to do.
I think that you would find, if you went into any VW Group dealership parts department and tried to buy a new petrol filter, they would need to order it in for you - so that for me points to them now not being a service item.
Of course places like ECP will probably have them in stock, from memory, VW Group seem to fit Chinese made petrol filters at the factories brand name might sound/look like USP or similar, for my money, I'd just buy a Mann/Hengst version if I wanted to replace it.