From memory with Model S/X production was 25,000 per quarter they were making the 75D variant.
My recollection is production rate dropped to 16,000 per quarter and the 3rd shift was dropped when they stopped making 75D.
From the Munro tear down of the Model S Plaid pack it contains a lot of 18650 cells, my impression is more cells than a Raven.
They could have stockpiled some 18650 cells, while production was shut or ramping, but my recollection is that form-factor can be used for Powerwalls.
Finally we had the prospect of a Plaid+ Model S at some stage using 4680 cells, or some other form factor. The Plaid+ was dropped, and I don't think it is likely that that decision is a whim. Dropping Plaid+ seems like a carefully considered reordering of priorities.
If cells are a constraint, sourcing more 18650 cells might be a path to higher production volumes.
When the 3rd shift was laid off, many would have been redeployed to other roles within Tesla, or left the company and got work elsewhere. No one was sitting by the phone waiting for a call.
It is likely some experienced Fremont staff have moved to Austin to help with the ramp there, and with training. So if staff are an issue, it can be fixed, but it isn't a quick fix.
It is likely some aspects of the ramp where "screwed up", they need to get all of the kinks out before sourcing more batteries, and hiring more staff.
Model X was always a complicated and difficult to build car. The refresh was an attempt to update the old platform with new components, while minimising changes to the body. Sometimes that is more difficult than a clean sheet design.
I'm not claiming that they are getting everything right, just that they are not making lazy mistakes, The mistakes are a result of high ambition, hard work, and a complex environment.
