Elon Musk is now working out of Twitter headquarters, thanks employees for long hours

On Friday, Twitter‘s new owner Elon Musk sent a companywide email to employees of the social media giant thanking them for working long hours since he took over on Oct. 28.

Musk said he had stayed at Twitter’s headquarters office in San Francisco late Thursday night as well. He then invited employees who have returned to the San Francisco office, after surviving last week’s 50% reduction in workforce, to come visit with him.

Overnight, Twitter appeared to pause its $7.99 per month Twitter Blue subscription service, which allowed users of the social network to pay to attain a blue verified-subscriber check mark. Many users abused the new subscriber badge to impersonate brands and famous people who acquired a blue check mark via the company’s original verification system.

Among the brands that were impersonated were pharmaceutical giant Eli Lilly, video game multinational Nintendo, and Musk’s electric vehicle company, Tesla.

Two current Twitter employees told CNBC that they were fielding calls from colleagues and clients about all the changes to the platform.

One said Twitter used to make product changes more slowly and carefully, because they had to balance user behavior, safety and revenue impact. The new, more experimental approach that Musk is taking has troubled many, including advertisers and even the Federal Trade Commission.

Employees also said they wanted more clarity about the company’s new time-off and return-to-office policies and that Musk’s e-mail left them with questions. Friday is a national holiday in the U.S., Veterans Day, and some workers did not expect they would have to come in, while others are wondering if they still have approved exceptions that will allow them to continue to work from home. Two employees told CNBC that they have not gotten formal guidance from the company’s human resources department on remote work.

Musk told Twitter employees Wednesday that he was reversing the company’s previous “work from home forever” policy, which had been enacted by his personal friend and collaborator, former Twitter CEO Jack Dorsey.

Here’s the e-mail from Musk to Twitter employees Friday, transcribed by CNBC: