TikTok could go dark in the United States on Sunday after the Supreme Court upheld a ban on the Chinese-owned social media platform — but it could be back as early as Monday. President-elect Donald Trump said he will “most likely” delay a ban on TikTok for 90 days after he takes office on Monday but noted he has not made a final decision in a phone interview with NBC News on Saturday.

Users on the app were saying their goodbyes, some filming themselves frantically scrolling or sharing final secrets with their followers ahead of the possible ban.