Year models of vehicles is a creation of the automobile industry. In most other equipment mfr’g the most important identification is the Serial Number or Build-Number.
Here’s a stoopid example: I own an airplane commonly known as a Cessna 170B. It’s official FAA registration certificate claims it to be a 1952 model. This is because it rolled off the assembly-line in Nov ‘52.
But it’s actually a 1953 year-model design with all the features introduced for 1953. As in the auto industry, next year’s “model” rolls off the assy-lines in the fall of the preceding year.
But when it was mfr’d in Nov ‘52 it was actually not registered in the U.S. It was shipped to El Salvador where it was first registered in any country’s aircraft registration system. After 20 years it was imported back into the U.S. by an Amoco Oil Co. employee and when he registered it with the FAA... it was issued a registration certificate which identified it as a 1973 Cessna 170B (because it was in 1973 that it first appears to have had registration requested of the FAA.). When I notified FAA that they had it WRONG... they “corrected” it to reflect it as a... 1952 model.
Clearly the FAA is dedicated to identifying an airplane’s model as in the year it first presents for registration.... having nothing to do with it’s design features or mfr’s identification by model year.
I think the bottom line for all us Kubota owners is that our tractor SERIAL NUMBER is more important than the actual date it rolled off an assy line, regardless of what some gov’t agency (EPA in this case) requires for it’s own paperwork issues.