12.—(1) Universal credit is payable in respect of each complete assessment period within a period of entitlement.
(2) In this Part an “assessment period” is a period of a prescribed duration.
(3) Regulations may make provision—
(a)about when an assessment period is to start;
(b)for universal credit to be payable in respect of a period shorter than an assessment period;
(c)about the amount payable in respect of a period shorter than an assessment period.
(4) In paragraph (1) “period of entitlement” means a period during which entitlement to universal credit subsists.