Even as Twitter said the sought-after blue check subscription service will be relaunched on November 29, billionaire owner Elon Musk has warned staffers that they should get ready to put in long hours in the office or are free to quit with a severance package.

Musk, according to a Reuters report, sent a message to Twitter Inc. staff telling them they had until Thursday to decide whether they wanted to stay on at the company to work “long hours at high intensity” or take a severance package of three months’ pay.

Musk told Twitter employees that anyone who had not clicked on a link confirming “you want to be part of the new Twitter” by Thursday evening New York time, would be considered to have quit.

A copy of the message, which was reported by The Washington Post, was reviewed by Reuters. Three sources who had received the message at Twitter confirmed its content.

Twitter did not immediately respond to a request for comment from Reuters.

The latest move to restructure the company comes after Twitter slashed half of its workforce earlier this month as Musk took control of the social media company. Musk has criticized Twitter’s spending and work culture, and said that the company needs steep cost cuts and a reboot of its services.

“Going forward, to build a breakthrough Twitter 2.0 and succeed in an increasingly competitive world, we will need to be extremely hardcore,” the message from Musk said.

“This will mean long hours at high intensity. Only exceptional performance will constitute a passing grade,” it added.

Musk said Twitter would be “much more engineering-driven” under his leadership, adding that “those writing great code will constitute the majority of our team and have the greatest sway”.

The billionaire CEO of Tesla Inc. has taken to cost cutting with a vengeance. Even after mass layoffs that forced it to attempt to offer some employees in critical divisions to return, some employees on Tuesday said they had been fired, which they suspected was due to posting critical comments on the company or Musk on Twitter or its internal message platform.

Musk called himself a “free speech absolutist” when he pursued the Twitter purchase.

The Blue Relaunch: Musk said on Tuesday that Twitter’s sought-after blue check subscription service will be relaunched on November 29, a minor delay from his initial tentative timeline to bring back the service on the social media platform.

“Punting relaunch of Blue Verified to November 29th to make sure that it is rock solid,” Musk said in a tweet.

With the new release, changing someone’s verified name will cause the loss of the blue check “until name is confirmed by Twitter to meet terms of service”, Musk said.

The coveted blue check mark was previously reserved for verified accounts of politicians, famous personalities, journalists and other public figures. But a subscription option, open to anyone prepared to pay, was rolled out earlier to help Twitter grow revenue as Musk fights to retain advertisers.

Twitter had paused its recently announced $8 blue check subscription service on Friday as fake accounts mushroomed. The change came a week after Musk took over the social media company in a $44 billion deal.