Bit of an update.

I bought a genuine second hand dpf for the car. I fitted it yesterday. Looking at the pics I think the aftermarket dpf is looking a bit blocked to me.

you can see the difference between the genuine one and the aftermarket dpf.

I've been out in the car today and the car did a regen. No smoke out the back of the exhaust like it was doing before. I've reset my trip computer and see how long it takes before the car does another regen.