The party does not need to wait. The three month period was intended to give EPA adequate time to process registrations. A party may proceed with production and importation after receiving an EPA registration number.(1/30/95)
This question and answer was originally posted at Consolidated List of Reformulated Gasoline and Anti-Dumping Questions and Answers: July 1, 1994 through November 10, 1997 (PDF)(333 pp, 18.17 MB, EPA420-R-03-009, July 2003, About PDF)