Where a return transfer order has been made under section 14 for the transfer of a prisoner from a State or Territory, the Attorney - General shall, by order in writing served, at any time before the commencement of the execution of the transfer order, upon the Superintendent or other officer in charge of the prison in which the prisoner is detained, revoke that transfer order if:
(a) the Attorney - General has ceased to be satisfied with respect to the matter referred to in paragraph 14(1)(a); or
(b) paragraph 14(1)(b) or (c) has ceased to apply in relation to the prisoner.