3(1)In sub-paragraph (2) of paragraph 26 of the said Schedule 5 (definition of unrecovered past stock relief) after " (2) " there shall be inserted the words " Subject to sub-paragraphs (3) to (5) below, " and after that sub-paragraph there shall be inserted—
“(3)There shall be excluded from the amount of unrecovered past relief in any period of account so much of that amount (if any) as is attributable to relief allowed under Part I or Part II of this Schedule in respect of any period of account which ended six years or more before the beginning of the first-mentioned period.
(4)There shall be excluded from the amount of unrecovered past relief in any period of account beginning after—
(a)the end of the period or last period of account ending in the financial year 1978 (in the case of a company) or the year 1978-79 (in other cases); or
(b)if there is no such period of account, the end of the period of account current at the end of that financial year or year of assessment, as the case may be,
so much of that amount (if any) as is attributable to Schedule 10 relief.
(5)For the purpose of attributing the amount of unrecovered past relief in any period to Schedule 10 relief or to relief allowed under Part I or Part II of this Schedule in respect of any previous period it shall be assumed that relief is recovered from later periods before earlier periods.”
(2)In sub-paragraph (5) of paragraph 25 of the said Schedule 5 (special provisions for the recovery of relief in cases of election for herd basis) for the words from the beginning to " made " there shall be substituted the words "(5) Subject to sub-paragraph (5A) below,
the amount on which the charge is to be made " and after that subparagraph there shall be inserted—
“(5A)The amount on which the charge is to be made in respect of any period of account (" the period of charge ") shall not exceed the amount of unrecovered past relief attributed to the herd at the point of election less—
(a)so much (if any) of the amount of that unrecovered past relief at that point as is attributable to relief allowed under Part I or Part II of this Schedule in respect of any period of account which ended six years or more before the beginning of the period of charge ; and
(b)if the period of charge begins after the end of the period of account mentioned in paragraph 26(4)(a) or (b) below, so much (if any) of the amount of that unrecovered past relief at that point as is attributable to Schedule 10 relief ; and
(c)the aggregate of the amounts on which charges have been made under this paragraph in respect of earlier periods of account for which the election has effect.”