(I) there is no spouse, (II) the participant and the participant's spouse have not been married for at least 1 year as of the date of the distribution or designation or change of beneficiary, or (III) such consent cannot be obtained because— (aa) the spouse cannot be located, or (bb) of such other circumstances as the Secretary, in consultation with the Secretary of Labor, may by regulations prescribe. (iii) Consent limited to spouse and event Any written consent by a spouse under clause (i), or the establishment by a participant that an exception under clause (ii) applies with respect to a spouse, shall be effective only with respect to that spouse and to the distribution or designation or change of beneficiary to which it relates. (iv) Consent period For purposes of this subparagraph, the term consent period means, with respect to any distribution— (I) the 90-day period immediately preceding the date of such distribution, or (II) such other period as the Secretary may provide. . 4. Effective dates (a) Increasing spousal protection under defined contribution plans Except as provided in subsection (b), the amendments made by section 3 shall apply to distributions and rollover contributions made in plan years beginning after the date that is 1 year after the date of the enactment of this Act. (b) Provisions relating to plan amendments (1) In general If this paragraph applies to any plan or contract amendment, such plan or contract shall be treated as being operated in accordance with the terms of the plan during the period described in paragraph (2)(C). (2) Amendments to which paragraph (1) applies (A) In general Paragraph (1) shall apply to any amendment to any plan or annuity contract which is made— (i) pursuant to the amendments made by section 3 or pursuant to any regulation issued under either such section