A social media platform used by 170 million Americans may go dark next month if the U.S. Supreme Court does nothing to stop a law banning or forcing the sale of TikTok from taking effect.

With the app’s shutdown or divestment required by Jan. 19, lawyers for TikTok, content creators and the government spent the holiday week furiously drafting their opening briefs in the high-stakes First Amendment case. The justices have set a lightning-fast briefing schedule and plan to hear the dispute on Jan. 10—a timeline more reminiscent of Bush v. Gore than a typical free speech case.