25 or so years ago when I asked on Cix if anyone knew why there were several seemingly unrelated businesses in Mile End called 'Advance'. Someone gave me a copy of the names from a phone book, and ADV (238) was indeed the original code for Bow and Mile End exchange from Director exchange days. While some names had a justification, others were arbitrary, such as that one. A wrinkle was that these numbers were changed in the 60s and the ADV exchange became 980, so 30 or so years later, there were still businesses (and quite possibly still are), whose names were inspired by an random choice of name in the 1950s. It was relatively common in London and I believe it happened in Liverpool and Birmingham as well, so quite possibly all areas that had satellite Director exchanges. A list of the names is here: https://rhaworth.net/phreak/tenp_01.php and there are links to the same lists from 60s phone books.