Tesla paused production of the Model S and X during the last week of February to perform “equipment maintenance” and install new machines for the Model 3, according to the company. It led to speculation coming from the supply chain that Tesla would start a pre-production run of the Model 3 at the same time.

We suspected that it would instead be a fleet of Model 3 ‘beta prototypes’, which Tesla has now confirmed.

In a SEC filing released yesterday following the company’s earnings for the fourth quarter 2016, Tesla confirmed that it hadn’t completed a Model 3 beta prototype during the period covered by the filing (December 31, 2016).

But the completion of the first Model 3 beta prototype is a milestone in Elon Musk’s CEO Grant and the board noted that it is expected to be achieved, which generally means in the next quarter or so (March 31, 2017).

Tesla added a note in the filing to confirm that those beta prototypes are part of the vehicles “currently” being built in Fremont:

“We expect that the next performance milestone to be achieved will be the successful completion of the Model 3 Beta Prototype, which would be achieved upon the determination by our Board of Directors that an eligible prototype has been completed. Candidates for such prototype are among the vehicles that we are currently building as part of our ongoing testing of our Model 3 vehicle design and manufacturing processes.“

The company didn’t disclose how many beta prototypes they are building, but in the case of Tesla’s last vehicle, the Model X, Musk said that it was over one hundred.

As mentioned, Tesla will use those prototypes to test the Model 3 and its manufacturing processes. If Tesla wants to stick to its schedule, the automaker will have a few months to fix any issues before moving to pre-production and start ramping up in July.

We reported earlier this week that based on its production plan, a perfect production execution means around 80,000 vehicles in 2017, but perfection is near impossible to achieve in this case.

Visually, the Model 3 beta prototype should be almost identical to the production version. Hopefully, we will spy one testing on public roads before the final reveal of the vehicle, which Musk pushed to “closer to the start of production”.

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