New Maxxis tires are 2 years old???

Hello, I enjoy reading topics on this forum and have learned a lot from you guys. This is my first post. With all the controversy of ST tires vs. LT tires, I decided to buy what many think are the best ST tires available since LT aren't an option in my size. I ordered 4 ST205/75R15 Maxxis M8008 tires from Summit Racing (a reputable company that was first to come up with google search) and got them today. I want to have the best experience with them. Checking them over, I found the last 4 digits of DOT # is "1314." They seem to be in brand new condition--must have been sitting around. So it appears they were made over 2 years ago, I'll call them tomorrow, but should I be concerned about this?

This is a little disconcerting since it shows a very slow timeline from manufacturer to customer. Are these tires moving that slowly with tire dealers like Discount or Les Schwab? I would think anything within a year would be acceptable, not sure about two years. The general rule of thumb is five years for RV tires and then replace. That means you really only have three years on these tires before you will start thinking about replacements if you follow the five year rule advice. Is that what you want?