Section 12.4 - When and how must documents be filed or issued?(a) Whenever this part requires or allows you to file a document on or before a certain date, you are responsible for submitting that document so as to reach the Government office designated for receipt by the time specified. You may use the U.S. Postal Service (USPS), a commercial carrier, or electronic or facsimile transmission. We will consider the document filed on the date on which the document is received by the Government office designated for receipt. Acceptable evidence to establish the time of receipt by the Government office includes any official USPS receipt, commercial carrier signature log, time/date stamp placed by the Government on the document, other documentary evidence of receipt maintained by that Government office, or oral testimony or statements of Government personnel.(b) Whenever this part requires or allows the Government to issue or file a document on or before a certain date, the document will be considered to be issued or filed on the date on which the document was placed in the USPS system, delivered to a commercial carrier, or sent by electronic or facsimile transmission. Acceptable evidence to establish the time of filing or issuance by the Government includes any official USPS sender's receipt, commercial carrier receipt log, and time/date stamp placed by the government office on the document, other documentary evidence of receipt maintained by that office, or oral testimony or statements of Government personnel.