(1)  A court, on its own motion, may cancel a drug treatment order (including such an order made by another court) as a reward if it is satisfied that –

(a) the offender has been fully or substantially complying with the conditions of the order; and

(b) the continuation of the order is no longer necessary to meet the purposes for which it was made; and

(c) the period of imprisonment that the offender would have had to serve had the order been fully activated at the time of sentencing has expired.

(2)  To avoid doubt, if a drug treatment order is cancelled under this section, any earlier orders activating the custodial part of the order cease to have effect forthwith.