You can find the petition at this link.
The petition alleges that the district court was going to convene a three-judge court until the Chief Judge of the 9th Circuit told the judge not to do so:
Petitioners claim no misconduct on the part of the district judge, the Chief Circuit Judge or any of the “attorneys” (presumably circuit staff attorneys) with whom the district judge had a “discussion” on this topic. Tr. of 6/14/2108 hearing at 29, Appendix at C-28a. Nevertheless, the Chief Circuit Judge did not have the benefit of briefing on this issue, and it is therefore a denial of due process for him to issue authoritative guidance to the district judge about how she must exercise her authority under 28 U.S.C. §2284(b)(1). Nor does the Chief Circuit Judge, acting in his administrative capacity under 28 U.S.C. §2284(b)(1), have authority to speak on this issue. Under the clear terms of the statute, his role is limited to “designat[ing] two other judges, at least one of whom shall be a circuit judge.” So whatever guidance or directive the Chief Circuit Judge gave to the district judge was ultra vires and injudicious.