Josh Ensign, the vice president of manufacturing at Tesla, has already left with no replacement named. Greg Reichow, Tesla’s vice president of production, plans to leave, but said he would stay on until the company finds someone to fill his job.

The exodus comes at a particularly sensitive time for Tesla, which is trying to increase production of the Model X crossover SUV, introduce a new version of the Model S sedan, and develop its mass-market car, the Model 3. Tesla has recently grappled with car recalls, production delays, as well as huge demand for the Model 3, a car that won’t even be available for nearly two years.

A Tesla spokeswoman declined to elaborate about Ensign’s departure.

A Tesla source familiar with the matter said the company had planned to discuss Reichow’s departure during an earnings call later in the day on Wednesday. However, the news of his departure leaked out early in a Bloomberg report.

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Reichow’s departure is being cast as a leave of absence and a natural stopping point for the executive who led production of the Model S and Model X. The development and eventually production of the Model 3, arguably Tesla’s most important car yet, is the next big project and one that would have locked Reichow in for several more years.

A spokeswoman emphasized that Reichow is not leaving due to production delays or a recent recall of the Model X. Tesla began deliveries of the Model X in September after months of delays. The company issued a recall last month of 2,700 Model Xs that were manufactured before March 26 due to an issue with the third row seats. Owners have also described widespread reliability issues with the SUV.

Tesla’s statement:

After being at Tesla for over five years and leading its production team for the past three years, Greg Reichow has announced his intention to take a leave of absence from Tesla so that he can have a well-earned break. To ensure a smooth handoff and provide continuity, Greg will remain at Tesla as long as necessary until his successor is on board. He will work closely with the Tesla leadership team to help with the search process and ultimately to make an effective transition to his successor. Tesla is currently identifying the best candidate to lead production into the launch of Model 3.

Tesla (TSLA) didn’t say when it hoped to have a replacement.

Reichow, who has led the production team for five years, said in a statement that bringing the Model S and Model X into high volume production is something he’ll always be extremely proud of.

Tesla, which is known as a demanding workplace, has caused many others before Reichow to quit. In recent months, a handful of other executives including James Chen, vice president of regulatory affairs and deputy general counsel, and Ricardo Reyes, vice president of global communications, have left.

What to expect from Tesla’s earnings today:

The company has a huge amount of work on its plate. And its most important test—production of the $35,000 Model 3—is fast approaching. There are already more than 400,000 refundable reservations for the Model 3, which won’t start shipping until the end of 2017.

Reichow’s departure does provide Tesla with an opportunity to find a candidate who has the kind of experience needed to manage the production of a high-volume mass market vehicle. Reichow had never worked at an automaker, which isn’t unusual for Tesla, a company known for recruiting professionals from the tech and energy industries. Prior to Tesla, Reichow was vice president of operations at solar power company SunPower, according to his LinkedIn profile. He also worked for a decade at Cypress Semiconductor.

Ensign didn’t have any direct automotive experience either, although he worked for Honeywell for more than a decade in a variety of supply chain, operations, and logistics positions.