Jeff Roberts, who shared the photos, said that those are production cars ready for transport.
As we can see, almost all of the cars are covered (some are in the process of being covered). We guess that those might be customer cars, envisioned for deliveries as soon as the company obtains the final certification for the Made-in-Texas Model Y.
The wheels, at least on some of the cars, appear to be the 19" Gemini Wheels, associated with the Model Y Long Range AWD version. 21" Überturbine Wheels would indicate the Performance version - some of those were recently seen leaving the plant.
It's expected that the next video flyover will give us a better view of the fleet and whether there will be a steady stream of new units.
The video, recorded on February 16 by Joe Tegtmeyer (below), also shows something very interesting - the 4680 battery production area on the 3rd floor.
The 4680 battery cells are the key differentiation between the Made-in-Texas and Made-in-California cars (equipped with 2170-type cylindrical cells).
The manufacturer did not reveal the specs or prices of the new Model Y from Austin. Because the 4680-type cells are supposed to be more energy-dense and more cost-effective, there is a big chance for higher range, higher power, quicker charging, etc.
There is also a second option - the specs will be the same (on paper), as the 4680-type battery pack will be simply smaller and lighter. In this scenario, Tesla would basically improve its margins to new record levels.