In reply to JB:
I emailed the enquiries address on their website and heard nothing. So I tried again two months later. Nothing. So, ten days later, I emailed the MD, and he arranged for them to do a repair FOC, which in the end turned into a replacement jacket (although of a different type, which I wasn't unhappy with). All I was after was a small piece of fabric to do a repair myself. I have to say that the third party repairers responded to an email within 24 hours.
So, although the end result for me was very good, their process does seem to be rather poor, a point I made quite strongly to the MD when thanking him for his eventual response. They also don't seem to support their third-party repairer by providing them with a source of matching fabrics.