Arriva National Fleet Numbering

[Barney]

Arriva National Fleet Numbering
A few years ago it seemed that Arriva was about to adopt a national fleet numbering system. Before its sale, Arriva Scotland began this process but since then Arriva seems to have decided not adopt such a system. Does anybody know why this is, considering both Stagecoach and First have had a five digit numbering system for several years?

When you consider the number of vehicles transferred between regions in any one year, it would seem logical for them to retain their original identity. By doing so it must surely be easier to be able to identify the mechanical history of each vehicle from a national data base and the recipient depot would know exactly what they were getting.