A date like that is more of a publicity thing anyhow. That's the " official" start. But they've been making them already. It's more of a gradual build up than a sudden beginning. It take months to weld bodies together and test them. Then send a few to be used for programming robots to do the painting and body sealer. Then actually seal and paint some and analyze them for quality. Paint a few and send them to the assembly shop to be built and test and fine tune robots and work methods there. Get some finished and sent for safety testing and early publicity teasers. Etc. Etc. Then once they start building actual normal production cars, the production numbers creep up gradually while final bugs in the process are still being ironed out.
Here at BMW, I saw the first X7 body come into the paint shop early last spring for programming. But I believe we just announced the official start of production within the past week or two. Even though I have seen hundreds of them get painted already.
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