All they told me was that I could not reuse them for any mailing purpose but Priority Mail. The punishment is you have to pay twice to mail that package LOL There is fine print somewhere on using these...and they COULD do more and they might...if they really wanted to. She pointed out the signs all over the PO regarding this service and the use of the boxes.
They can be reused over and over with the PO's blessings as long as they are ALWAYS mailed as Priority :wink: