; and (ii) the designated beneficiary shall be treated as an eligible designated beneficiary for purposes of applying section 401(a)(9)(H)(ii) of the Internal Revenue Code of 1986 (as in effect after such amendments). (B) Effective date For purposes of this paragraph, the term effective date means the first day of the first calendar year to which the amendments made by this subsection apply to a plan with respect to employees dying on or after such date. (b) Provisions relating to plan amendments (1) In general If this subsection applies to any plan amendment— (A) such plan shall be treated as being operated in accordance with the terms of the plan during the period described in paragraph (2)(B)(i); and (B) except as provided by the Secretary of the Treasury, such plan shall not fail to meet the requirements of section 411(d)(6) of the Internal Revenue Code of 1986 and section 204(g) of the Employee Retirement Income Security Act of 1974 by reason of such amendment. (2) Amendments to which subsection applies (A) In general This subsection shall apply to any amendment to any plan or which is made— (i) pursuant to any amendment made by this section or pursuant to any regulation issued by the Secretary of the Treasury under this section or such amendments; and (ii) on or before the last day of the first plan year beginning after December 31, 2021, or such later date as the Secretary of the Treasury may prescribe. In the case of a governmental or collectively bargained plan to which subparagraph (B) or (C) of subsection (a)(4) applies, clause (ii) shall be applied by substituting the date which is 2 years after the date otherwise applied under such clause. (B) Conditions This subsection shall not apply to any amendment unless— (i) during the period— (I) beginning on the date the legislative or regulatory amendment described in paragraph (1)(A) takes effect (or in the case of a plan amendment not required by such legislative or regulatory amendment, the effective date specified by the plan)