SCOTUS can move much quicker than this when they want to.

And have fairly regularly to benefit this administration:

https://en.wikipedia.org/wiki/Shadow_docket#Second_Trump_pre...

https://en.wikipedia.org/wiki/J.G.G._v._Trump was vacated within days.

"On Friday, March 14, 2025, Trump signed presidential proclamation 10903, invoking the Alien Enemies Act and asserting that Tren de Aragua, a criminal organization from Venezuela, had invaded the United States. The White House did not announce that the proclamation had been signed until the afternoon of the next day."

"Very early on Saturday, March 15, the American Civil Liberties Union (ACLU) and Democracy Forward filed a class action suit in the District Court for the District of Columbia on behalf of five Venezuelan men held in immigration detention… The suit was assigned to judge James Boasberg. That morning, noting the exigent circumstances, he approved a temporary restraining order for the five plaintiffs, and he ordered a 5 p.m. hearing to determine whether he would certify the class in the class action."

"On March 28, 2025, the Trump administration filed an emergency appeal with the US Supreme Court, asking it to vacate Boasberg's temporary restraining orders and to immediately allow the administration to resume deportations under the Alien Enemies Act while it considered the request to vacate. On April 7, in a per curiam decision, the court vacated Boasberg's orders…"

TL;DR: Trump signs executive order on March 14. Judge puts it on hold on March 15. Admin appeals on March 28. SCOTUS intervenes by April 7.

That was on the emergency docket. This decision was the merits docket, which always takes much longer.