Operating Areas:
CM (Chelmsford), DA (Dartford), E (East London), EC (City of London)), EN (Enfield), IG (Ilford), N (North London), NW (North West London), RM (Romford), SE (South East London), SW (South West London), W (West London), WC (West Central London), WD (Watford)
Operating Areas:
AL (St. Albans), BR (Bromley), CM (Chelmsford), CR (Croydon), DA (Dartford), E (East London), EC (City of London)), EN (Enfield), GU (Guildford), HA (Harrow), IG (Ilford), KT (Kingston upon Thames), N (North London), NW (North West London), RH (Redhill), RM (Romford), SE (South East London), SL (Slough), SW (South West London), TN (Tonbridge), TW (Twickenham), W (West London), WC (West Central London), WD (Watford)