Changes made by Transport Act 1980 (Commencement No. 4) 1981
S.I. 1981/256
Made to Transport Act 1980 (Commencement No. 1) 1980
2 changes. All changes made by Transport Act 1980 (Commencement No. 4) 1981
From legislation.gov.uk's record of changes, the official one: see it there.