Challenge to legislative district apportionment, three-judge district court, standing

QUESTIONS PRESENTED 1. In a case challenging the constitutionality of the apportionment of legislative districts, may a district judge, sitting alone, decide a motion to dismiss for lack of standing or, rather, does this Court's unanimous opinion in Shapiro v. McManus, 136 S. Ct. 450 (2015), require that that motion be decided by a three-judge district court convened pursuant to 28 U.S.C. §2284(a)? 2. May the Chief Circuit Judge interfere with a district judge’s exercise of responsibility pursuant to 28 U.S.C. §2284(b)(1) by instructing the district judge to withdraw the notice issued pursuant to that section and decide the motion to dismiss as a single-judge district court?