336.An election under section 334 and a revocation of the election shall be made in prescribed form containing prescribed information and shall specify the effective date thereof.
336.An election under section 334 is effective for the period beginning on the first day of the reporting period referred to in paragraph 1 or 2 of section 335 and ending on the earliest of
(1) the day the member or the corporation ceases to be a member of the closely related group;
(2) the first day of the calendar year in which the member or the corporation ceases to qualify as a specified member of the group; and
(3) the day the member or the corporation specifies in a notice of revocation in prescribed form containing prescribed information filed with and as prescribed by the Minister by the member or corporation, which day is
(a) not before the end of the calendar year of the person filing the notice in which the election became effective; and
(b) where the notice is filed on or before the day on or before which a return for a reporting period under Chapter VIII is required to be filed by the person filing the notice, the first day of that period.