This and previous rumors/unofficial reports (CNBC) lists a whole bunch of possible upgrades of the next-generation S/X:
- three-motor powertrain (1 in the front and two in the rear)
- new battery pack (possibly with new 2170 cylindrical cells) and more capable cooling ("currently being tested under extreme heat")
- more range of up to around/over 400 miles (644 km) in case of Model S and close to 400 miles in case of Model X (EPA)
- capability to charge at full power from V3 Superchargers (250 kW)
- refreshed exterior and interior, following minimalist Model 3 design
- production form September
- production of Model S/X on a single line, instead two separate to make space for Model Y
For us, the Tesla Model S and Model X are really the state-of-the-art EVs and, after the most recent refresh, their leading position strengthened. Having more upgrades would be kind of overkill in terms of competitive advantages, but who knows - maybe the changes on the production lines forced by the addition of Model Y are a good opportunity to make a bigger refresh to the S/X and a necessity to increase sales to peak levels/or at least higher margins.
In terms of rumored changes, we guess that all are reasonable, maybe besides the three-motor concept. Two rear motors would open a way for more power, torque vectoring and in general better performances in top of the line versions, although it brings additional cost and complexity.
The biggest issue with Tesla rumors could be the Osborne effect that could prompt customers to wait for the rumored car and collapse current sales.