A court may not make a detention and training order as a result of which the offender would be subject to relevant detention and training orders for a term exceeding 24 months.
Where—
a court makes a detention and training order, and
the term of the relevant detention and training orders to which the offender would otherwise be subject exceeds 24 months,
the excess is to be treated as remitted.
Where—
a court makes a detention and training order, and
as a result the offender is subject to two or more relevant detention and training orders,
the terms of those orders are to be treated for the purposes of sections 241 to 243 ... and Schedule 12 as a single term.
See section 248 for the meaning of “relevant detention and training order”.