6. The function of the Secretary of State under section 199 is transferred—
(a)where it is exercisable by virtue of section 199(1)(a) in any case in which the offence or one of the offences is an offence under section 4 or 57(3) of the Act, and
(b)where it is exercisable by virtue of section 199(1)(b) in any case in which the requirement referred to in that enactment is one which has been imposed by the designated agency or by a person authorised by it under section 106 of the Act.