Thanks Ed

I thought this was the more likely case, but the sensor plugs in from the back of the hub and appeared to be flush up against the back plate

I am thinking that this is probably a cheap aftermarket sensor being sold as a Genuine part, but in reality is probably no longer manufactured for this vehicle

The garage that fitted it has spoken to TPS, but they are not interested, they told him to book it into a VW dealer to make a claim

Peter