Re: Telephone Number Songs

"Lumpy" <lumpy@[EMAIL PROTECTED]
> writes:
>Note that the prefixes AT and CU are both the
>same numbers "28". But the billing was still
>tied to the alpha exchanges AT or CU.

The exchange was the first three digits, whether they were expressed as
digits
or letters.  In the early days they chose exchange codes that made sense
as
three-letter prefixes, e.g., ATL(antic) = 285.  But as the demand for
telephones grew, they ran out of those, so (without actually changing
anything
in the equipment) they renamed ATL as AT5 (ATlantic 5), so that they could
also use AT2, AT3, etc., even if those numeric codes didn't have
meaningful
three-letter representations.