Talk to your dealer. They can write up the sale to occur on a date you agree to as long as it’s close to actual delivery date. They do this in cases where they want to book the sale for end of month / quarter when the car will be delivered a few days later. They offered it to me to help them quarter end (they were going to throw in floor mats for my accommodation) but I didn’t do it.I am just about to freeze my build today, with delivery in early January. But I am also curious about the tax credit. Does one pay for the car upon delivery, which in both of our cases would be early 2021? Or does one pay when the vehicle hits the port (in December)? I searched the web but couldn't find any definitive answers.