They'll also bring new manufacturing processes to their new factories. Musk said on the latest earnings call that new factories are building "better cars" with

They'll also bring new manufacturing processes to their new factories. Musk said on the latest earnings call that new factories are building "better cars" with all the latest enhancements. So while Fremont might keep making "original" model 3, I think it's likely other new factories will skip straight to the new processes. So for example the factory in Berlin will just start with a monster press like this on day 1, so all Model Y built there will automatically have the "new" design. Same for the Model 3 and Model Y lines in Texas.