The oil standard VW 508.00 / 509.00 describes new smooth-running oils with specification SAE 0W-20. These oils are not backwards compatible, so they must not be used in older, unapproved engines! This oil can be used only in 2018 model year GTI, GTI PP petrol engines, but not “R” engines!
Some model year 2017 cars had partly false information in the manual (saying that it is compatible), so VW started to mark engines that cannot tolerate this oil since then with an appropriate sticker in the engine compartment.
In case of doubt, ask the dealer/workshop!
VW 504.00 / 507.00 is safe in any case for 2017 & 2018 model year cars.