Nothing in Parts II to IV shall—
(a) be construed as affecting a provision to which this subsection applies, or
(b) render unlawful an act which is done in order to give effect to such a provision.
Subsection (1) applies to a provision for conferring benefits on persons of one sex only (disregarding any benefits to persons of the opposite sex which are exceptional or are relatively insignificant), being a provision which is contained in a charitable instrument.
But subsection (1) does not apply to discrimination under section 1 or 2A in its application to sections 29 to 31 unless the conferral of benefits is—
(a) a proportionate means of achieving a legitimate aim, or
(b) for the purpose of preventing or compensating for a disadvantage linked to sex.