Elon Musk added to his work portfolio late last year, when he acquired Twitter for $44 billion and appointed himself CEO. While he recently announced a successor for that role, the job is currently still his, and he remains the CEO of Tesla and SpaceX.

He talked about trying to manage his schedule in an interview on Tuesday at the The Wall Street Journal’s CEO Council Summit.

“My days are very long and complicated as you might imagine,” Musk said. “And there’s a great deal of context switching,” he said, emphasizing that “switching context is is quite painful.”

Musk said he generally tries to divide his schedule “so it’s predominantly one company on one day.”

But that’s not always possible. This Tuesday was “a Tesla day,” he said, but he “might end up at Twitter late tonight, and then tomorrow would be partly a Tesla day as well, half Twitter and then Thursday would be sort of a half-SpaceX, half-Tesla day.”

He described his jobs as “somewhat intertwined,” and said “the time management is extremely difficult.”

The complexity hasn’t been good for his investments. Tesla shares lost more than half their value in the two months after the Twitter deal closed last year, on concern that Musk would have less time to focus on the electric car maker even as the market was getting more competitive. Meanwhile, advertisers fled or temporarily suspended their campaigns on Twitter, and in March Musk marked down the value of the company to $20 billion. Musk said on Tuesday that many advertisers are coming back.

While other executives may outsource their calendar to a chief of staff or executive assistant, Musk said he does most of his scheduling on his own. He said he has “one part-time assistant” to help him manage his work schedule, a fact that was corroborated by a former Tesla employee.

“It’s impossible for someone else to know what the priorities are,” Musk said, adding that he is usually working most hours of the day, wrapping up at 2 a.m., his typical bedtime.

At Twitter, Musk now plans to shift into the role of executive chairman and technology chief, with former NBC ad executive Linda Yaccarino slated to become CEO.

However, Twitter is primarily a technology company, so his ongoing job as CTO will likely be demanding.

Thorold Barker, The Wall Street Journal’s editor for Europe, Middle East and Africa, asked Musk if he has a succession plan in place at his businesses.

“Succession is one of the toughest, age-old problems,” Musk said. “It’s plagued countries, kings, prime ministers and presidents, and CEOs since the dawn of history.”

Musk said he’s told his boards, “in all cases,” who is his choice to take over in a “worst-case scenario.” He emphasized the companies’ boards could also go in another direction as far as who should step into his shoes.

At Tesla, there’s been speculation that finance chief Zachary Kirkhorn is among candidates who Musk would endorse as a successor.

As CNBC previously reported, Musk’s companies frequently engage in related party transactions, and he’s faced political pressure to more cleanly separate them.

After Musk took over Twitter, for example, he authorized dozens of employees from Tesla, SpaceX and the Boring Co. to help him at the social media venture. The “transition team” he established at Twitter was involved in everything from code review to personnel and facilities-related decisions.

Musk was also a co-founding director and donor to OpenAI, a former non-profit that’s now backed by Microsoft. Financial filings from 2017 for OpenAI reveal that Musk donated around $250,000 worth of Tesla vehicles as part of his millions of dollars worth of donations to OpenAI back in its earlier days.

Of late, Musk has been openly attacking OpenAI’s corporate structure and the amount of ownership it’s sold to Microsoft. On Tuesday, Musk talked some about X.ai, a competitor he wants to develop in order to challenge OpenAI, and Google’s DeepMind.

“I don’t want to jump the gun here on announcements,” Musk said. “But OpenAI has a relationship with Microsoft that seems to work fairly well, and it’s possible that X.ai and Twitter and Tesla would have something similar.”

（Picture: Veer）