If we're taking the "Model 3 Group 1" as an example of Model 3 retrofits starting, it does match up with prioritizing earlier VINs, here 004xxx, as opposed to starting from the newest cars built this year.
While the "Model S and Model X Group 1" was first reported back in September with an April 2018 build date. 2017 Q4 was around hardware 2.5 was introduced and had 28k S/X deliveries, and 2018 Q1 had 22k S/X, so maybe "Group 1" includes 50k-75k VINs. Although with those sizes, S/X Group 2 could be the remainder of 2018 S/X and early 2019 S/X VINs; whereas Model 3 delivered that many in various quarters, so there could be many more Groups.
And for those even earlier with MCU1/HW2.0, looks like Tesla is still figuring out what to do.
![Frown :( :(](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Although some people seem to have suggested those vehicles will get MCU upgraded as part of the FSD retrofit.
Have there been any reports of Mobile Service completing a FSD computer upgrade?