Now that he owns Twitter, Elon Musk has given employees their first ultimatum: Meet his deadline to introduce paid verification on Twitter or pack up and leave.

The directive is to change Twitter Blue, the company’s optional, $4.99 a month subscription that unlocks additional features, into a more expensive subscription that also verifies users, according to people familiar with the matter and internal correspondence seen by The Verge. Twitter is currently planning to charge $19.99 for the new Twitter Blue subscription. Under the current plan, verified users would have 90 days to subscribe or lose their blue checkmark. Employees working on the project were told on Sunday that they need to meet a deadline of November 7th to launch the feature or they will be fired.

Musk has been clear in the months leading up to his acquisition that he wanted to revamp how Twitter verifies accounts and handles bots. On Sunday, he tweeted: “The whole verification process is being revamped right now.”

Platformer’s Casey Newton first reported that Twitter was considering charging for verification. A spokesperson for Twitter didn’t respond to a request for comment by press time.

Even though he is barely three days into being “Chief Twit,” Musk has moved quickly to make changes at Twitter, first by changing its homepage for logged out users. With the help of Tesla engineers he has brought into Twitter as advisors, he’s also planning mass layoffs aimed at middle managers and engineers who haven’t recently contributed to the code base. Those cuts are expected to begin this week with managers already creating lists of employees to cut. Employees tasked with executing projects of Musk’s since he took control Thursday evening have been working late into the night and over the weekend.

The Twitter Blue subscription launched widely almost a year ago as a way to view ad-free articles from some publishers and make other tweaks to the app, such as a different color home screen icon. In the few quarters that Twitter reported earnings as a public company after that debut, advertising remained the vast majority of its revenue. Musk is keen on growing subscriptions to become half of the company’s overall revenue, The Verge reports.