Defra have produced further guidance on TB catle movement controls and common land.
Briefly, if you are in an annual testing area fom 30 June 2014 all cattle aged over 42 days of age must be pre-movement tested before moving to and from common land.
For movements back from the common, farmers can carry out a post-movement test instead to reflect the fact that in most cases, TB testing on common land is impractical and dangerous.