In this section—
Day A is the day on which the complainant or applicant concerned complies with the requirement in subsection (1) of section 18A of the Employment Tribunals Act 1996 (requirement to contact ACAS before instituting proceedings) in relation to the matter in respect of which the proceedings are brought, and
Day B is the day on which the complainant or applicant concerned receives or, if earlier, is treated as receiving (by virtue of regulations made under subsection (11) of that section) the certificate issued under subsection (4) of that section.
In working out when the time limit set by section 123(1)(a) or 129(3) or (4) expires the period beginning with the day after Day A and ending with Day B is not to be counted.
If the time limit set by section 123(1)(a) or 129(3) or (4) would (if not extended by this subsection) expire during the period beginning with Day A and ending one month after Day B, the time limit expires instead at the end of that period.
The power conferred on the employment tribunal by subsection (1)(b) of section 123 to extend the time limit set by subsection (1)(a) of that section is exercisable in relation to that time limit as extended by this section.