>>10114625 U.S. Treasury makes $10 billion loan available to postal service as part of chinavirus relief, lb notable
I am pretty sure that the USPS is not a Federal agency.
United States Post Office Department
https://en.wikipedia.org/wiki/United_States_Post_Office_Department
"The United States Post Office Department (USPOD; also known as the Post Office or U.S. Mail) was the predecessor of the United States Postal Service, in the form of a Cabinet department, officially from 1872 to 1971. It was headed by the Postmaster General."
If some of the information I have is correct, then the Postmaster General has to be set up before commerce can be opened.