I received the latest IEE newsletter a few days ago, and the adoption of the new colors was one of the articles.
Where cables conforming to the new color code are to be joined to existing (old color) cables, they are proposing the following re-identification of conductors (with tape, sleeves, etc.):
Existing red, yellow (or white), and blue phases be tagged brown. Existing black neutrals be tagged blue. New black and gray phases be re-identified brown.
In other words, where new and old cables meet, identification will be applied such that all phases will be brown and all neutrals will be blue.
I suppose this is logical in its own way, but I still see room for mistakes here.
