3.—(1) Under paragraph 1(6) of Schedule 1 to the Act, a person shall be disregarded for the purposes of discount on a particular day if–
(a)on the day the person is imprisoned, detained or in custody under the Army Act 1955(1), the Air Force Act 1955(2) or the Naval Discipline Act 1957(3); and
(b)the conditions prescribed in paragraph (2) are fulfilled where they are applicable.
(2) The conditions are that, where a person is in custody under arrest under any of the Acts mentioned in paragraph (1)–
(a)the person is not in custody under open arrest; and
(b)the custody forms part of a continuous period exceeding 48 hours during which the person is under arrest.
(3) A person is to be treated as in custody under open arrest for the purposes of paragraph (2)(a) if the person is so treated for the purposes of Queen’s Regulations for the Navy, Army or Air Force.