Elon Musk is now facing a new crisis at Twitter as a wave of employees seemed to reject his ultimatum of an “extremely hardcore” Twitter 2.0 or leave the company.

Hours after a deadline for workers to check “yes” on a Google form accepting “long hours at high intensity, it seems a large number of employees have rejected Musk’s vision.

Exactly how many employees opted for severance over remaining at Twitter isn’t yet clear. The New York Times reported the number was in the “hundreds,” while other early reports suggest the number could be much higher.

The departures come after Musk already cut 50 percent of Twitter’s jobs in mass layoffs.

On Twitter, dozens of Twitter employees who had survived the initial round of layoffs tweeted farewell messages.

One employee tweeted a video of a group of workers inside Twitter’s office counting down to the 5 pm ET deadline on Musk’s ultimatum. “We’re all about to get fired,” he said.

Others tweeted messages alluding to Musk’s policies. In his Wednesday morning message, Musk had said that “only exceptional performance will constitute a passing grade.”

As the deadline approached, Musk reportedly grew concerned about how many remaining employees could leave the company.

In a new memo, he appeared to walk back some of his earlier comments banning all remote work, though he still said he would fire managers if remote workers on their teams weren’t performing.

But it seems the concession wasn’t enough for many at Twitter Platformer’s Zoe Schiffer reported Thursday that Musk and his lieutenants were struggling to figure out just how many employees had declined to check the “yes” box on his Google form, and that Twitter would be closing down access to its offices for a few days as an extra precaution.

The departures raise new questions about whether the remaining Twitter engineers will be able to reliably keep the service up and running. Current and former employees are already speculating that the latest exodus could further put Twitter’s ability to function at risk, especially with the start of the World Cup a few days away.

Twitter no longer has communications staff, but Musk so far hasn’t publicly commented on the resignations.