In article , Richard J.
writes
It may have something to do with the fact that people have no idea what
ITU or E.123 are. Please provide a reference to these alleged
standards.

That could be so. Have you heard of a body called the United Nations?
Well the International Telecommunications Agency, ITU, is one of its
technical agencies, with headquarters in Geneva. Its website can be
found at http://www.itu.int

Unfortunately you have to pay (CHF 20 I seem to remember) to get a copy
of any of its main documents - but you can at least see a list of them
free by digging down in the web-site. There used to be an unofficial (I
guess illegal) copy of E.123 on the web, but it seems to have vanished -
maybe a more careful search would still find one. No doubt a good many
technical libraries keep copies of all ITU documents, and may even allow
you to photocopy E.123.

Not true. Since there was at that time an 0181 222 exchange as well as
an 0171 222 exchange, the 222 xxxx format would not have been unique.

I think you mis-understand - such numbers were unique within their own
zone. During the transitional period, as I already pointed out, London
continued to have the same 7-digit dialling as it had been using since
the 1930s. It was not until the second change that the local numbers
changed from being 7-digit to 8-digit, and then they became unique
across the whole city, not just in the single zone.

I doubt it. Do you have any evidence of official approval of "0207 xxx
yyyy" formats?

Of course not: officially the double transition did not exist, which has
led directly to the current confusion. This form was only valid during
the period between the first change, which introduced the area codes
starting 020 and the second one which changed from 7-digit to 8-digit
local numbers. But the rules of ITU E.123 are clear that the space
should always be shown between the area code and the local number.
During the transitional period of some six months that was after the
0207 or 0208.


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Clive Page