Thanks MH I appreciated your advice.
The interview was very informal and I liked the Director from the start, he was very laidback and welcoming. The questions revolved around my past and present qualifications and what my present position in my company involved. I did a bit of a presentation showing a couple of products I have designed, this worked quite well as they were able to talk about some of their projects. At the end we talked about how I would finance the PhD and whether my company would be willing to support me (hopefully they will!) this was followed by a tour of the facilities, which were very impressive. The interview went so well I can’t really believe it. I think that they will change their minds so until I receive a formal offer through the post I won’t be counting my chickens.
I emailed them yesterday accepting their (verbal) offer to start this year and asked what I needed to do next, so I am holding my breath waiting for a reply.