Hi Simon.
Your grandmother would be Joan Paley I guess? You can contact me via my website from my genealogy pages at
http://www.stevenberry.org/genealogy/. This site will of course be of interest to to Brian since it may contain Yewdalls that are missing from his list (BTW Brian, I tried contacting Beverley on Genesreunited but have never received a response - this was about 6 months ago now).
I am actually in the process of updating the Yewdalls and fixing many of the census references that are currently incomplete (these were recorded missing the folio number when I first started building my family tree).
Looking forward to hearing from you.
Cheers,
Steven.