this is correct, you canot join the same day, and try to buy the truck
you could join dec1, and use it dec 31st. if your truck was just built,and hasnt been shipped, as shipping usually takes 3-5 weeks in most cases.
can you just use the old expired certificate, and the dealer click "protection date" in Vincent? if your truck was ordered in 2023, but delivered example in feb 2024?