45 CFR §148.124

1. (a)General rule. The rules for providing certificates of creditable coverage and demonstrating creditable coverage have been superseded by the prohibition on preexisting condition exclusions. See § 147.108 of this subchapter for rules prohibiting the imposition of a preexisting condition exclusion.
2. (b)Applicability. The provisions of this section apply beginning December 31, 2014.