(1) Is adopted no later than 2 and one-half months after the close of such plan year (or, in the case of a multiemployer plan, no later than 2 years after the close of such plan year),

(2) Does not reduce the accrued benefit of any participant determined as of the beginning of such plan year, and

(3) Does not reduce the accrued benefit of any participant determined as of the time of adoption of the amendment, or, if it does so reduce such accrued benefit, it is shown that the plan administrator filed a notice with the Secretary of Labor notifying him of the amendment, and—

(1) The election under section 412(c)(8) shall be made by the plan administrator by a statement of election described in subparagraph (3) of this paragraph, attached to the annual return relating to minimum funding standards required to be filed under section 6058 with respect to the plan year to which the election relates.

(2) In the event that an amendment to which paragraph (a) of this section applies is adopted after the filing of the annual return required under section 6058, the plan administrator may make the election under section 412(c)(8) by attaching a statement of election, described in paragraph (b)(3) of this section, to a copy of such annual return, and filing such copy no later than the time allowed for the filing of such returns under section 6058. (In the case of multiemployer plans, such copy may be filed within a 24 month period beginning with the date prescribed for the filing of such returns.)

(3) The statement of election filed by or on behalf of the plan administrator shall—