Tesla never said they will be building today's batteries in the plant and I would be surprised if your assumption is correct. They likely have projections on their R&D and can also project how long it takes to build massive capacity on what they are building.
All major manufacturers of all complex products are faced with the same challenges. Management must match R&D to production or they will have huge misses. Manufacturing true technologically advance products is tough.
There are many examples of companies that simultaneously invest in R&D while making far out production capacity investments: Intel, all Pharmaceutical companies etc. etc.
If you can think of some companies that invest heavily in R&D, then stop investing in R&D and start investing in manufacturing, I would be interested in learning about them and why.