Strange one, spoke to few who have not came across this.
VCDS shows 01800 E1 Headlight Switch (implausible signal)
Tried a switch from another B7 with no auto lights etc and still was the same.
Wiring all appears good but will be giving it another check.
Could it be the J519 module just gone bad, it's looking like that but wan't to be 100% before ordering.
Worth swapping from another car, just a case of keeping the long coding to hand.