In Archon v. Eight Jud. Dist. Ct., 133 Nev. Adv. Op. 101 (2017), the Nevada Supreme Court provides a concise explanation of the uses of mandamus and administrative mandamus as escape hatches from the final judgment rule. The background of the case is a bit weird, but it involved a suit by the preferred stockholders of a corporation alleging that the corporation had incorrectly calculated the redemption price. After the plaintiffs won on summary judgment, the corporation successfully moved to dismiss the suit for want of subject matter jurisdiction (the amount in controversy was slightly less than the $5 million required by 28 U.S.C. § 1332(d)). At that point, the plaintiff in the Nevada action filed his own complaint and the defendants moved to dismiss based on the running of the statute of limitations. The trial court denied the motion based on "cross jurisdictional tolling" and other grounds. The defendants then sought review through by seeking advisory mandamus from the Nevada Supreme Court.
The Nevada Supreme Court refused to grant extraordinary writ relief, explaining:
Mandamus is an important escape hatch from the final judgment rule, but such relief must be issued sparingly and thoughtfully due to its disruptive nature. Advisory mandamus, like any form of interlocutory review, carries the significant negative risks of delaying the ultimate resolution of the dispute and undermining the "mutual respect that generally and necessarily marks the relationship between . . . trial and appellate courts". Bauman v. U.S. Dist. Court, 557 F.2d 650, 653 (9th Cir. 1977).
This is not the end of the road for the defendants. As the Supreme Court pointed out, they will have further opportunities to present their arguments at summary judgment, or to the Supreme Court on appeal or, even, in another writ petition depending upon discovery and the eventual substantive motion practice that may ensue.
Giving a hand to mandamus
For the etymology of "mandamus" and California's two forms of mandamus, see this post from August, 2016.