Tim-don't forget the subsidised beer prices.
Looking at the "Y" prefix on station names, I always led to believe that "YAB" WOULD BE A RADIO STATION AT "AB"( FICTIONAL NAMES), whereas repeater stations started with the station name (e.g. AB/A) and each new one received the next letter in the alphabet as a /suffix. Any poster on here from a GPO/PO TRS background will remember the number of CEL 6 buildings ( same sixe as UAX ) that littered the main routes from town to town, each with their own building name .
From memory ( and not a lot of knowledge of those horrible places where things went clunk click = exchanges), I remember that the same code would be used without any suffixes for places with only one exchange.