On 16 Feb, 17:40, Sacha wrote:

R. Jackman's is unknown to me or to Ray or the
Plant Finder or Google.

I knew I hadn't imagined it and would find it. Check this link to find
Jackman's Prostrate which is so like the one you describe. I'll get
some pictures of it from a friend. The leaves are a bit broader and
waxy. The catalogue pdf gives you details of it.

http://www.burncoose.co.uk