(1) Where a person to whom pension benefit has become payable (whether or not it has become payable to the person by virtue of section 78) would, but for this section, be entitled to an increase in the rate at which the pension benefit was payable to the person immediately before the commencement of the prescribed half - year and:
(a) if the pension benefit became payable to the person otherwise than as a spouse or as an eligible child--the pension benefit became payable to the person during the half - year (in this section referred to as the preceding half - year ) immediately preceding the prescribed half - year;
(b) if the pension benefit became payable to the person as the spouse of a member of the scheme and pension benefit in accordance with that section was not payable to the member immediately before his death--the pension benefit became payable to the spouse during the preceding half - year;
(c) if the pension benefit became payable to the person as the spouse of a member of the scheme and pension benefit was payable to the member immediately preceding his death--the member's pension benefit became payable during the half - year;
(d) if the pension benefit became payable to the person as an eligible child and pension benefit was not payable to the member of the scheme in relation to whom the person is an eligible child--the pension benefit became payable to the child during the preceding half - year; and
(e) if the pension benefit became payable to the person as an eligible child and pension benefit was payable to a member of the scheme in relation to whom the person is an eligible child--the member's pension benefit became payable during the preceding half - year;
this section applies to the first - mentioned pension benefit.
(2) Where a pension benefit is, under section 43A or 44, payable to a person immediately before the commencement of a prescribed half - year:
(a) in a case where the pension benefit became so payable by virtue of the retirement and death, during the preceding half - year, of a member of the scheme who was, at the time of his death, a recipient member--this section applies to the pension benefit as if it were a pension benefit payable to the person otherwise than as a spouse or as an eligible child from the day following the date of retirement of the member of the scheme;
(b) in a case where the pension benefit became so payable by virtue of the death, during the preceding half - year, of a member of the scheme who was, at the time of his death, a contributing member--this section applies to the pension benefit as if it were a pension benefit payable to the person otherwise than as a spouse or as an eligible child from the day following the date of death of the member of the scheme; or
(c) in any other case--this section does not apply to the pension benefit.
(3) If:
(a) the pension benefit;
(b) where paragraph (1)(c) applies--the pension benefit that was payable to the member of the scheme in relation to whom the person is a spouse; or
(c) where paragraph (1)(e) applies--the pension benefit that was payable to the member of the scheme in relation to whom the person was an eligible child;
became payable after 16 June or 16 December (as the case requires) in the preceding half - year the person is not entitled to the increase.
(4) If:
(a) the pension benefit;
(b) where paragraph (1)(c) applies--the pension benefit that was payable to the member of the scheme in relation to whom the person is a spouse; or
(c) where paragraph (1)(e) applies--the pension benefit that was payable to the member of the scheme in relation to whom the person was an eligible child;
became payable on or before 16 June or 16 December (as the case requires) in the preceding half - year, the amount of the increase is so much only of the amount that, but for this section, would have been the amount of the increase as bears to that last - mentioned amount the same proportion as the number of months in the period that commenced on the day on which the pension benefit referred to in paragraph (a), (b) or (c) became payable and ended on 30 June or 31 December (as the case requires) in the preceding half - year bears to 6.
(5) If the period referred to in subsection (4) is less than 1 month, that period shall be treated as 1 month.
(6) If the period referred to in subsection (4) consists of a number of whole months and a part of a month:
(a) where the number of days in that part of that month is less than one - half of the number of days in that month--that part shall be disregarded; and
(b) where the number of days in that part of that month is not less than one - half of the number of days in that month--that part shall be treated as a whole month.