In other words, Tesla rather breaks a customer promise, instead of selling me a new car.
You're in the right.
Forum members here are going to make a lot of excuses for Tesla acting like jerks... "you should know Tesla by now". Just because cool Elon shoots cars into space, does not make it ok to treat you like that. They added an expiration date after the fact. That's deceit. This should not be not be accepted by anyone... and I doubt we'd be seeing excuses made if this were Kia.
Talk to a lawyer.