I've always found it interesting to find out about former route numbers, etc.
A few I know of for definite;
Service 778 - now Service 78
Service 551 - now Service 50
Service 734 - now Service 34
The whole 722/23/24 thing has always confused me. Was the 724 Newcastle-Bishop Auckland and the 723 Newcastle-Darlington?
Go North East: Latest News & Discussion - April 2015