This regulation does not apply to electric supply service provided by a utility before the service periods stated in §B of this regulation. A utility shall provide Type III large customer service to customers for the following specified time periods: Baltimore Gas and Electric Company from July 1, 2004 through May 31, 2005; Delmarva Power & Light Company from June 1, 2004 through May 31, 2005; Potomac Electric Power Company from July 1, 2004 through May 31, 2005; and The Potomac Edison Company doing business as (d/b/a) Allegheny Power from January 1, 2005 through December 31, 2005.