This section applies where a court imposes a sentence of detention under section 250 or 252A in the case of an offender who is subject to a relevant detention and training order.
If the offender has not at any time been released for supervision under the relevant detention and training order, the court may order that the sentence of detention is to take effect at the time when the offender would otherwise be released for supervision under the relevant detention and training order (see section 248(5)).
Otherwise, the sentence of detention takes effect at the beginning of the day on which it is passed.
In this section “relevant detention and training order” means—
a detention and training order under section 233,
an order under section 211 of the Armed Forces Act 2006 (corresponding order under that Act), or
an order under section 100 of the Powers of Criminal Courts (Sentencing) Act 2000 (detention and training order: offender convicted before the commencement of this Act).