no scheme for the payment of allowances shall be submissible under subsection (5) of section 51; and

a scheme which has been approved under that subsection of that section shall forthwith be revoked under subsection (6)(b) of that section, so however that where a person was before its revocation receiving payments made in accordance with that scheme he may continue to receive payments so made which, had there been no revocation, would have fallen to be made to him or he may agree to receive, instead of the continued payments, payments made in accordance with an adoption allowances scheme.