In article , Charlie Pearce
writes
But the area codes were *never* 0207 and 0208 - this is just a (very)
commonly-held misconception because the changeover wasn't communicated
well enough.

Well we are getting in to questions of semantic, I fear, as to the
meaning of "dialling code". I still think that during the transition
period, when the local numbers were 7 digits long, and one could call
them by starting dialling 020... that, following the rules of the ITU
E.123, the space in the number should have preceded the local part of
the number, i.e. before the last seven digits. So that the number could
have been given either as 0171 xxx yyyy or with equal validity 0207 xxx
yyyy.

It wasn't until London got eight-digit local dialling that the former
code vanished, and the space moved to a point before the 7 (or 8). Of
course Oftel didn't support this, and it's a somewhat pedantic point,
but it seems undeniable, if you read E.123 carefully.

--
Clive Page