The Council Tax Benefit Regulations 2006

2.  The conditions prescribed in this paragraph are that the claimant or the claimant’s partner—

(a) notifies either the designated office or an appropriate DWP office that he or his partner—

(i) has commenced, or is about to commence, remunerative work;

(ii) has commenced, or is about to commence, receiving remuneration for work or an increased amount of remuneration for work; or

(iii) has commenced, or is about to commence, an increased number of hours of work,

so that entitlement to income support or to an income-based jobseeker’s allowance ceases and that work or, as the case may be, remuneration, is expected to last 5 weeks or more; and

(b) makes that notification no later than 4 weeks after the day on which the claimant or his partner first undertakes the remunerative work referred to in sub-paragraph (a)(i) or first receives remuneration for the work or an increased amount of remuneration for the work referred to in sub-paragraph (a)(ii), or first commences the increased number of hours of work referred to in sub-paragraph (a)(iii).