As stated above, KTAC and "warranty" are not the same thing.
Very similar to a your car insurance through State Farm Vs. Chryslers 3/36 vehicle warranty. They both cover your vehicle, but for different circumstances.
I took the 0% for 84 months and have KTAC for the entire 84 months, however I am no longer covered under Kubota warranty. (which I believe was 2 years?)
So if my water pump sh!ts out, I have to pay to fix it myself, but if I roll it down a hill KTAC will buy me a shiny new one......
At the time that made sense, I have no idea what the offer/cash rebate is nowadays though.