Twice in the past two months the Supreme Court has construed activity, or inactivity, in the district court as tantamount to issuing, or refusing to issue, a preliminary injunction and thus appealable.

In Dep't of Educ. v. California, 2025 U.S. LEXIS 1370, at *1-2 (U.S. April 4, 2025), it was a TRO that was deemed tantamount to a preliminary injunction and thus appealable:

On March 10, 2025, the United States District Court for the District of Massachusetts issued what it styled as a temporary restraining order (TRO) enjoining the Government from terminating various education-related grants....

Although the Courts of Appeals generally lack appellate jurisdiction over appeals from TROs, several factors counsel in favor of construing the District Court’s order as an appealable preliminary injunction. Among other considerations, the District Court’s order [***2]  carries many of the hallmarks of a preliminary injunction. See Sampson v. Murray, 415 U. S. 61, 87, 94 S. Ct. 937, 39 L. Ed. 2d 166 (1974); Abbott v. Perez, 585 U. S. 579, 594, 138 S. Ct. 2305, 201 L. Ed. 2d 714 (2018). Moreover, the District Court’s “basis for issuing the order [is] strongly challenged,” as the Government is likely to succeed in showing the District Court lacked jurisdiction to order the payment of money under the APA. Sampson, 415 U. S., at 87, 94 S. Ct. 937, 39 L. Ed. 2d 166

In A.A.R.P. v. Trump, 2025 U.S. LEXIS 1837, at *3 (U.S. May 16, 2025), it was inaction as tantamount to refusing an injunction:

"Appellate courts have jurisdiction to review interlocutory orders that have 'the practical effect of refusing an injunction.' Carson v. American Brands, Inc., 450 U. S. 79, 84, 101 S. Ct. 993, 67 L. Ed. 2d 59 (1981). A district court’s inaction in the face of extreme urgency and a high risk of 'serious, perhaps irreparable,' consequences may have the effect of refusing an injunction."