UPS recycles all of their tracking numbers. Sometimes, for a full day after a tracking number is assigned to a new package, the information available will pertain to a previous order that traveled -- sometimes months ago -- under that same number.
When this happens, please rest assured that your tracking information will be available within a short period of time and should indicate the correct delivery date. Once the package is scanned by UPS, you will also be able to click the "view package progress" link, and the updated tracking detail will be reflected.