USPS Automatic Shipment Status (Google Sheet)

I created this Google Sheet to automatically pull the status of USPS tracking numbers without using any special services. Meaning it is completely self-operating and does not use any API connections or other software. It uses Google Sheets very own "importXML" command which grabs webpage data from URLs based on what are called Xpath queries put together by programmers such as myself. Since these queries depend on the data being located at a specific point in the webpage code there is the distinct possibility that they could stop giving the desired result at some point in the future if the webpage undergoes changes. However, as long as I am still doing this I will work to update it accordingly. Please notify me of any issues or experiences you have with this sheet. Thank you.