Endymion Ponsonby-Withermoor III typed:
Clive D. W. Feather wrote:

There are countdown signs on the approaches to some villages near
where I live: the usual diagonal stripes with a speed limit sign
above, except that the red ring is grey (presumably to stop it being
a speed limit sign).

When I first saw one of those combined "countdown and speed-limit"
signs, I interpreted it as "there is a speed limit HERE, because
there is a junction in x00 metres", not "there will be a speed limit
in x00 metres"

When countdown signs for temporary speed limits on motorways were first
introduced, they had a black circle instead of a red one, which made it
clear that it wasn't an immediate change of limit. But nowadays, the
circles are red, which leads to the confusion you describe. I often see
what appears to be a speed limit sign, and ease off my speed, and then
notice that it's not for 300 yards because it's got three little stripes
below it. Not a good design, I feel.
--
Richard J.
(to e-mail me, swap uk and yon in address)