Pre 1950s rides of LFGSS: old bikes, vintage rats, classic lightweights

Isn't that seat stay cluster more Carlton-ish?

Or maybe it's a forgery (replica with Hetchins decals) with lugs made by Len (http://www.classiclightweights.co.uk/builders/phipps-builders.html)

Or it could be (it's not) Len's own frame built by Ron as per link above :)

Anyway according to this: http://www.hetchins.org/302b.htm it could be a 1959ish frame:

1951 to 1961. In 1951 the system was changed. 'H' replaced all but the last digit of the year
(195)1, so H1 stood for 1951. For 1952, the prefix was 'E2'; the first 49 frames for 1953 had a
'T2' prefix, the last frame with this code being T24508--the 4,508th frame counting from
August 1935; as before, the last four digits carried on the production sequence numbering.
Apparently, Hetchin intended to carry on with C, H, I, N, and S prefixes. However, after
T24508, the sequence carried on from frame number H24509, and subsequent 1950s
frames all had 'H2' prefixes strong text (although a few frames are known from this period without the
leading 'H'). This carried on until the end of 1961.

And below there's a frame number as an example: H26955, 1957 or 8.
And then one more: H28112, 1960.
This is an H27632.

So now off to see the lugs patterns for that period of time.