Hi Poppybat
I may be mistaken but I seem to remember my father working in a house opposite the old gasworks in Valley Road Cinderford when it was being used as offices for Northern United Colliery. This was in the late 50's early 60's. I am 80% sure this was Bilson House. If that was the case then a bit of research into Northern United might reveal something and sincere apologies if I am wrong.
Is there anyone else out there who can confirm this?.
Dave