In other words, it is a big job for even an experienced exec and the cupboards are pretty bare at Uber.

The company has no COO, CFO, CMO or SVP of engineering and all of those vacancies are without accounting for the possible terminations that several sources suspect will happen as a result of the Holder report. In addition, several sources at Uber said attrition among the rank-and-file staff has spiked.

If Kalanick does temporarily step away from his role, there are very few people left at the company who could easily step in and run it in his stead — particularly if Uber SVP of business Emil Michael is fired or gives into pressure from the board and resigns .

Uber's board is currently meeting with lawyers from Covington and Burling to discuss the results of a months-long investigation into the car-hailing company's culture. Among the topics on the docket is whether Uber CEO Travis Kalanick should take a three-month leave of absence.

But, among those who are left at the company, several people have suggested that Rachel Holt, the general manager of U.S. and Canada, could take over in the interim. Holt has been at the company since 2011, working her way up the ladder from general manager of Washington D.C. These people did question whether she was equipped to run the whole company, however, due to her lack of experience in key areas.

Instead, one source said the board could decide to install a committee to manage the company rather than a single executive. Candidates for that committee include members of the A team — or Kalanick's trusted insiders — like Andrew Macdonald, the regional manager for the Asia Pacific and Latin America and the head of product Daniel Graf. Other potential members are the company's head of Europe, Middle East and Africa Pierre-Dimitri Gore-Coty and the company's chief human resources officer Liane Hornsey.

Then there are the possible board members who might be able to temporarily take the reigns such as Arianna Huffington, Garrett Camp or Bill Gurley.

Camp, Kalanick's co-founder, hasn't been heavily involved in the company's operations, sources said. As for Gurley and Huffington, it's unclear whether they'd take on the role or if either is remotely qualified to run such a big and complex organization like Uber.

There's also the possibility that Ryan Graves — the company's former CEO and later former president — could take back the position, given his previous experience running the company. That's only if the Holder report doesn't result in his termination, because of his one-time purview of its troubled human resource org. Both he and the company's CTO Thuan Pham have come under pressure in the investigation, we reported earlier.

However, Graves — who is also a board member — has been frequently away from the office, several sources said, and has less of a hand in the company's day-to-day operations.

Uber also recently hired noted academic Frances Frei to be its SVP of leadership, who seems very unlikely to be able to take over for Kalanick.

And it's very unclear, still, how temporary this temporary leave of absence will be. It's also a trying time for Kalanick who recently suffered personal tragedy when his mother died in a boating accident. His father, too, was injured and in critical condition.

Another twist: Kalanick — who has had effectively control of Uber's board — might try to resist and stay on.

That will be the hardest choice. By most measures, Uber has already had a bad year under his troubled leadership. Save for its business — which the company proudly revealed has narrowed its losses from $991 million to $708 million in the first quarter of 2017 — the ride-hail company valued at $69 billion has publicly begun to reckon with the consequences of an overly aggressive culture or at least come up against the limitations of it.

In the words of Hornsey, it's the "confidence to be bold" (read: take-no-prisoners attitude) that got the company to where it is today. But that is also precisely what is undoing it.

"Looking closely at our culture, it's absolutely a truism that every strength in excess can become a weakness," Hornsey said. "Uber is disruptive — and disruption demands the confidence to be bold. What I have seen, though, is that this has translated internally to what I would call a cult of the individual. We now need to expend genuine effort ensuring the individual is never more important than the team — not ever."

That cult of the individual came from the very top from Kalanick. The hyper-competitive executive and serial entrepreneur is notoriously combative and has difficulty unclenching his grip on the reins of the company.

He might now have no choice.

In order to navigate the increasingly murky waters that the company's culture has wrought, however, the Uber board was searching for a chief operating officer — a mature adult to whip the company into shape. That person is meant to be a "true partner" to Kalanick, board member Arianna Huffington said during a press call in March, although much of the evidence points to his continued reluctance to let anyone else call the shots at the company.

However, the difficult COO search — made more difficult by the possibility of the CEO stepping away — has yet to be completed.

In other words, the company has little by way of options for temporarily replacing Kalanick.

—By Johanan Bhuiyan, Re/code.net.

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