(1) This subsection applies in any case where the Secretary of State would have jurisdiction to make a maintenance calculation with respect to a qualifying child and a non-resident parent of his on an application duly made ... by a person entitled to apply for such a calculation with respect to that child.
(2) Subsection (1) applies even though the circumstances of the case are such that the Secretary of State would not make a calculation if it were applied for.
(3) Except as provided in subsection (3A), in any case where subsection (1) applies, no court shall exercise any power which it would otherwise have to make, vary or revive any maintenance order in relation to the child and non-resident parent concerned.
(3A) Unless a maintenance calculation has been made with respect to the child concerned, subsection (3) does not prevent a court from varying a maintenance order in relation to that child and the non-resident parent concerned—
(a) if the maintenance order was made on or after the date prescribed for the purposes of section 4(10)(a) or 7(10)(a); or
(b) where the order was made before then, in any case in which section 4(10) or 7(10) prevents the making of an application for a maintenance calculation with respect to or by that child.
(4) Subsection (3) does not prevent a court from revoking a maintenance order.
(5) The Lord Chancellor or in relation to Scotland the Lord Advocate may by order provide that, in such circumstances as may be specified by the order, this section shall not prevent a court from exercising any power which it has to make a maintenance order in relation to a child if—
(a) a written agreement (whether or not enforceable) provides for the making, or securing, by a non-resident parent of the child of periodical payments to or for the benefit of the child; and
(b) the maintenance order which the court makes is, in all material respects, in the same terms as that agreement.
(5A) The Lord Chancellor may make an order under subsection (5) only with the concurrence of the Lord Chief Justice.
(6) This section shall not prevent a court from exercising any power which it has to make a maintenance order in relation to a child if—
(a) a maintenance calculation is in force with respect to the child;
(b) the non-resident parent’s gross weekly income exceeds the figure referred to in paragraph 10(3) of Schedule 1 (as it has effect from time to time pursuant to regulations made under paragraph 10A(1)(b)); and
(c) the court is satisfied that the circumstances of the case make it appropriate for the non-resident parent to make or secure the making of periodical payments under a maintenance order in addition to the child support maintenance payable by him in accordance with the maintenance calculation .
(7) This section shall not prevent a court from exercising any power which it has to make a maintenance order in relation to a child if—
(a) the child is, will be or (if the order were to be made) would be receiving instruction at an educational establishment or undergoing training for a trade, profession or vocation (whether or not while in gainful employment); and
(b) the order is made solely for the purposes of requiring the person making or securing the making of periodical payments fixed by the order to meet some or all of the expenses incurred in connection with the provision of the instruction or training.
(8) This section shall not prevent a court from exercising any power which it has to make a maintenance order in relation to a child if—
(a) an allowance under Part 4 of the Welfare Reform Act 2012 (personal independence payment) or a disability living allowance is paid to or in respect of him; or
(b) no such allowance is paid but he is disabled,
and the order is made solely for the purpose of requiring the person making or securing the making of periodical payments fixed by the order to meet some or all of any expenses attributable to the child’s disability.
(9) For the purposes of subsection (8), a child is disabled if he is blind, deaf or dumb or is substantially and permanently handicapped by illness, injury, mental disorder or congenital deformity or such other disability as may be prescribed.
(10) This section shall not prevent a court from exercising any power which it has to make a maintenance order in relation to a child if the order is made against a person with care of the child.
(11) In this Act “ maintenance order ”, in relation to any child, means an order which requires the making or securing of periodical payments to or for the benefit of the child and which is made under—
(a) Part II of the Matrimonial Causes Act 1973;
(b) the Domestic Proceedings and Magistrates’ Courts Act 1978;
(c) Part III of the Matrimonial and Family Proceedings Act 1984;
(d) the Family Law (Scotland) Act 1985;
(e) Schedule 1 to the Children Act 1989; ...
(ea) Schedule 5, 6 or 7 to the Civil Partnership Act 2004; or
(f) any other prescribed enactment,
and includes any order varying or reviving such an order.
(12) The Lord Chief Justice may nominate a judicial office holder (as defined in section 109(4) of the Constitutional Reform Act 2005) to exercise his functions under this section.