I suppose I should post what I've posted at folkinfo as part of trying to find a answer.

A couple of answers for you Ian from my limited range of pamphlets.

1967- Spring 68 Were produced by George Dixon.
Autumn 68 to the end of my collection (Summer 86) were produced by Douglas Coombes"
The last one I have wich credits William Appelby as broadcaster is Autumn 1970.