Rules phased in over 3 years.—

In the case of the portion of an account to which subparagraph (C) applies and which consists of employer securities acquired in a plan year beginning before January 1, 2007 , subparagraph (C) shall only apply to the applicable percentage of such securities. This subparagraph shall be applied separately with respect to each class of securities.

Subclause (I) shall not apply to an applicable individual who is a participant who has attained age 55 and completed at least 3 years of service before the first plan year beginning after December 31, 2005 .