13. Where a supervision order is in force in respect of any person and, on the application of the supervised person or the supervising officer in accordance with regulation 12 above, it appears to a magistrates' court acting for the local justice area concerned or (as the case may be) a judicial officer that, having regard to circumstances which have arisen since the order was made, it would be in the interests of the health or welfare of the supervised person that the order should be revoked, the magistrates' court or the judicial officer may revoke the order.