Each district court shall conduct a continuing study of the administration of criminal justice in the district court and before United States magistrate judges of the district and shall prepare plans for the disposition of criminal cases in accordance with this chapter. Each such plan shall be formulated after consultation with, and after considering the recommendations of, the Federal Judicial Center and the planning group established for that district pursuant to section 3168. The plans shall be prepared in accordance with the schedule set forth in subsection (e) of this section.