Its 100% a 2021 production and if it is consider yourself very fortunate, the 2021 productions have the least number of parts and modules missing plus you will get the LithiumIron instead of LithiumIon battery which has had many complaints to date, it will also have the Intel Atom MPU which on surface appears slower due to advertised frequency yet consumes less power due to the fact it has an onboard GPU versus the newer which has an external GPU. If it is in fact 2021 leftover which was either cancelled and not collected or a showroom vehicle (not demo) grasp it with all life and consider yourself very lucky as you will not only not have to wait months for your car but you will receive a higher quality production. Many people will most certainly disagree as they believe the 2022 is a better car as it has more recent changes. With Tesla, unfortunately changes are not always good or better, they are simply changes required to yield the vehicle manufactured and out the door on to a ship, 2300 of them per day in normal operating conditions
How would it be possible you would know it's 100% a 2021 production, unless there's a VIN given?
I wouldn't be accepting an Intel Atom car now, that would mean it'll be missing various improvements that go along with that build,