As of now, all such rallies must adhere to the rule that "competitors must be seeded numerically in order of their anticipated performance."
That means no more split fields with 2WD or smaller capacity cars, running ahead of 4WD or larger capacity machinery.
This will apply UK-wide. Full text of MSA Press Release here:
http://www.jaggybunnet.co.uk/2015/03/7229/