Can you provide a link to some of the other docs? I only ask because someone with military background questioned using the PO Box in the letterhead, saying they would normally use the street address on the official letterhead. (They also pointed out that the letterhead should show the parent organization, not the squadron.)
Thread is Per FoxNews: Pentagon questioning PO Box Number -- Post #49
Click This -- Letterhead for 147th FIG with PO BOX 34567 address is about 3/4 of the way down the docs.