Ah, rattles!
I wasnt here for a couple of months. I come back and see rattles

Some things never change.
The outside temp is a big factor for rattles. Everything's expanding and moving.
I've had number of problems back in September, all fixed by VW. There is something coming from the boot but I will get it in the end.
The other thing is the roads quality or rather lack of it. Potholes are not good for rattles. I takes sometimes one big bump to get some rattling parts going.
Take it to the dealer, have it fixed. They sold you the car, they have to fix it. I've gone through this and it works.