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I know someone that was undergoing training for BMW in the US recently, and they booted the whole lot of them out as they didn't have study visas."
Some of that training can be done under an H-3 visa. In your case, the B-1/B-2 isn't normally permitted for initial training. I posted the regulations and text from the State Department's Foreign Affairs Manual on this in
M1 Visa or no Visa and SEVIS approved schools in the USA
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Previously an ESTA would have been suitable..."
It's been a long time since that was permitted for initial training.