“(1) The entitlement of the person or persons by whom a claim for working tax credit has been made is dependent on him, or either or both of them, being engaged in qualifying remunerative work. (2) Regulations may for the purposes of this Part make provision— (a) as to what is, or is not, qualifying remunerative work, and (b) as to the circumstances in which a person is, or is not, engaged in it. (3) The circumstances prescribed under subsection (2)(b) may differ by reference to— (a) the age of the person or either of the persons, (b) whether the person, or either of the persons, is disabled, (c) whether the person, or either of the persons, is responsible for one or more children or qualifying young persons, or (d) any other factors.”
“(7) Any power to make regulations under this Act may be exercised— (a) in relation to all cases to which it extends, to all those cases with prescribed exceptions or to prescribed cases or classes of case, (b) so as to make as respects the cases in relation to which it is exercised the full provision to which it extends or any less provision (whether by way of exception or otherwise), (c) so as to make the same provision for all cases in relation to which it is exercised or different provision for different cases or classes of case or different provision as respects the same case or class of case for different purposes, (d) so as to make provision unconditionally or subject to any prescribed condition, (e) so as to provide for a person to exercise a discretion in dealing with any matter. … (9) Any power to make regulations or a scheme under this Act includes power to make any incidental, supplementary, consequential or transitional provision which appears appropriate for the purposes of, or in connection with, the regulations or scheme.”
“(1) Subject to the qualification in paragraph (2), a person shall be treated as engaged in qualifying remunerative work if, and only if, he satisfies all of the following conditions (and in the case of the Second condition, one of the variations in that condition).”
“(1A) For the purposes of interpretation of paragraph (1)— … (b) regulations 5, 5A, 6 and 7A and 7B apply in relation to periods of absence from work connected with childbirth or adoption, sickness, strike periods or suspension from work; (c) regulation[…] 7C appl[ies] where pay is received in lieu of notice; (d).
“(1) This regulation applies for any period during which a person— (a) is paid maternity allowance, … (2) For the purposes of the conditions of entitlement in this Part, the person is treated as being engaged in qualifying remunerative work during the period. This is subject to paragraphs (3), (3A) and regulation 7D . (3) The person must have been engaged in qualifying remunerative work immediately before the beginning of the period. (3A) [not material to the present case]”
“(1) This regulation applies for the four-week period immediately after— (a) a person, not being a member of a couple, who is engaged in qualifying remunerative work for not less than 16 hours per week, ceases to work or starts to work less than 16 hours per week, … (2) For the purposes of the conditions of entitlement in this Part, the person is treated as being engaged in qualifying remunerative work during that period.”
“For the purposes of the conditions of entitlement in this Part a person shall be treated as being engaged in qualifying remunerative work for the requisite number of hours if he has been so engaged within the past 7 days.”
“where a person is treated as being in qualifying remunerative work during these periods so as to be entitled to Working Tax Credit, their entitlement will extend to all elements of Working Tax Credit to which the individual or couple claiming were formerly entitled. This will include the childcare element where the other conditions for entitlement to that element are met.”
“(2). For the purposes of the conditions of entitlement in this Part, the person is treated as being engaged in qualifying remunerative work during that period.”