Civil Defence Corps "R" inside knotted rope badge

[londonclanger]

I recently added a page to my civil defence website about Civil Defence Corps badges (although my main interest is WW2, I get more requests to ID CDC badges).

I've utilised both the information and some images previously shared on this forum.

One last badge to ID conclusively is the "R" inside a knotted rope. I've see a few suggestions but had nothing concrete regarding this badge. Anyone know the full SP on this badge?

Cheers

Craig