Section 69 of the [1955 c. 18.] Army Act 1955 and section 69 of the Air Force Act 1955 (act conduct or neglect to prejudice of good order and military or air force discipline) shall each be amended by omitting the word " act "; and section 39 of the Naval Discipline Act 1957 (act, disorder or neglect to prejudice of good order and naval discipline, being one not described in the foregoing provisions of that Act) shall be amended by substituting the word " conduct " for the words " act, disorder", by omitting the words " not described in the foregoing provisions of this Act ", and by substituting the words " imprisonment for a term not exceeding two years " for the words " dismissal with disgrace from Her Majesty's service ".