4(1)Where a rebate or an allowance is first granted, the rebate period or allowance period shall commence at the commencement of the rental period in which the application for a rebate or an allowance was received.
(2)A rebate period and an allowance period shall end, subject to paragraphs 5 and 6 below—
(a)if the tenant is of pensionable age, not later than twelve months after the date on which he was notified that his application for a rebate or an allowance was granted ; and
(b)in any other case, not later than six months after that date.