Referees are only as good as the last time they stepped on the mat. It’s important that referees practice their skills regularly at events appropriate to their level and attend national referee seminars to update their knowledge.
British Judo will automatically revalidate referees if they have met the revalidation criteria for their level at the end of two-year revalidation cycle on 1 January each biennial year. Typically this requires a referee to officiate at a certain number of events at a particular level every two years.
Full details of the revalidation criteria can be found in the Refereeing Handbook which can be downloaded here