If Roadster is to be assembled in Fremont on the new S/X "Palladium" line, then its 4680 cell supply will almost certainly come from Kato Rd (10 GWh/yr planned capacity).
So, Roadster can go into production as soon as Giga Texas is independant for 4680s. Obviously, Semi can use some of those Kato cells in the first years of production, until the 2nd larger Semi GA line is running in Austin.
TL;dr I expect to hear a basic update on 4680 progress from the 30,000' level, with some fog near the Arpt...
Cheers!