They have a deadline in about a month to reveal what exactly their "reserves" are comprised of, could be the moment.
This has been going on for years, and it seemed that nobody was able to force them to prove anything.
https://www.bloomberg.com/news/articles/2021-02-23/crypto-ex...
>New York officials, who originally began investigating Bitfinex in 2019, will receive quarterly reports on composition of Tether’s reserves for the next two years. The companies will end all trading activity with New Yorkers.
That starts in about a month
There's nothing in the article that suggests that tether will be closed if they are not backed up 100%, so I guess it won't make any real change even if they are not.