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.”

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.

Update October 30th at 9:25PM ET: Added detail that existing verified users will lose their checkmark in 90 days if they don’t subscribe to the new Twitter Blue after it launches.