Sorry, you don't know what you're talking about. There are several types of VIN assignments. Sold orders (which are customer orders), dealer stock orders, allocated orders, etc. Dealers place orders for lot inventory in most cases. Customer orders are actually pretty rare. And allocations are for items with limited availability - an example being the special edition TRX's. Ram would build 1000 or so, and let the dealers know how many each were getting.
And no, they don't batch them for efficiency. I have never worked in a manufacturing plant (construction is my business), but I have studied the output of the Sterling Heights plant for several years and I can assure you that I have a better idea of what they build than you do.
Here's an example to put this business to rest. Model year 2022. Production started on 9/13/21. TRX's were in the mix on the first day. And the second day. I've split them by "sold order" and all "other" types so you can see what they built. I'm only showing the first 28 days, but I can assure you the entire model year was like that. Do you see any batch of customer orders? I don't.
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