As I understand it the changes to CAP 371 are based on research by QinetiQ carried out in 2001 in response to concerns about fatigue in short haul operations. The airlines have until to 2006 to implement the changes in the CAP.
Of course, in the intervening years the problems which concerned the CAA (and pilots like myself) have remained.
The process is too slow.
I support the changes to CAP 371 but the ethos of the document is such that an airline can still write a truly awful roster and get away with it.