For purposes of subparagraph (A) and section
1086
(c) of this title, any plan amendment made pursuant to a collective bargaining agreement relating to the plan which amends the plan solely to conform to any requirement contained in this chapter or title 26 shall not be treated as a termination of such collective bargaining agreement. This paragraph shall not apply unless the Secretary determines that the participation and vesting rules in effect on September 2, 1974, are not less favorable to participants, in the aggregate, than the rules provided under sections
1052,
1053, and
1054 of this title.