27Reviews under s. 25 - supplementary
(1)Regulations—
(a)may prescribe what are, or are not, relevant changes of circumstances for the purposes of section 25 above; and
(b)may make provision restricting the payment of any benefit, or any increase of benefit, to which a person would, but for this subsection, be entitled by reason of a review in respect of any period before or after the review (whether that period falls wholly or partly before or after the making of the regulations).
(2)Regulations under subsection (1)(b) above shall not restrict the payment to or for a woman of so much of—
(a)any widow’s benefit, any invalidity pension under section 40 of the Contributions and Benefits Act or any Category A or Category B retirement pension; or
(b)any increase of such a benefit or pension,
as falls to be paid by reason of a review which takes place by virtue of section 25(1)(a) or (1)(b) above in consequence of a claim for a widowhood benefit, within the meaning of section 3 above, which is made or treated as made by virtue of that section.