(1)An employee who presents a complaint of unfair dismissal alleging that the dismissal is unfair by virtue of section 152 may apply to the tribunal for interim relief.
(2)The tribunal shall not entertain an application for interim relief unless it is presented to the tribunal before the end of the period of seven days immediately following the effective date of termination (whether before, on or after that date).
(3)In a case where the employee relies on section 152(1)(a) or (b) the tribunal shall not entertain an application for interim relief unless before the end of that period there is also so presented a certificate in writing signed by an authorised official of the independent trade union of which the employee was or proposed to become a member stating—
(a)that on the date of the dismissal the employee was or proposed to become a member of the union, and
(b)that there appear to be reasonable grounds for supposing that the reason for his dismissal (or, if more than one, the principal reason) was one alleged in the complaint.
(4)An “authorised official” means an official of the trade union authorised by it to act for the purposes of this section.
(5)A document purporting to be an authorisation of an official by a trade union to act for the purposes of this section and to be signed on behalf of the union shall be taken to be such an authorisation unless the contrary is proved; and a document purporting to be a certificate signed by such an official shall be taken to be signed by him unless the contrary is proved.
(6)For the purposes of subsection (3) the date of dismissal shall be taken to be—
(a)where the employee’s contract of employment was terminated by notice (whether given by his employer or by him), the date on which the employer’s notice was given, and
(b)in any other case, the effective date of termination.