Apologies for my lateness in updating this.

We did try the method mentioned but was struggling to get it to regenerate. Unfortunately the customer was desperate to get the car fixed so had authorised us to fit a new (non-genuine) DPF.

The first one we tried was physically to big (only 10mm extra in length) and would just not fit despite the part manufacturer saying it would. A slightly more expensive one from another supplier fitted fine and vehicle is now happy again.

I'm sure if we could have had the car longer we may have been able to get the regeneration to work but having the time to take it out onto a suitably long test road (i.e. motorway) when you're located 30 mins drive from the nearest one is always going to be a problem.

Thank you to everyone who took the time to reply.

Regards

Sean