Two anecdotal pieces of evidence to suggest this: 1.) A member on the forum mentioned he bought the upgrade and got a new MCU, which was missing the bubbles from his old MCU 2.) I am trying to get a goodwill replacement of my screen. They asked "is it 3G or LTE" so they know which replacement to order. Does this suggest that an LTE upgrade is actually an MCU swap? Perhaps they send the old MCU back to Tesla to be refurbished with LTE for the next person (much like the DU milling issue). If this is true, then I should be able to buy the LTE upgrade and get a screen replacement in the process... Can anyone confirm?