[DuncanWaring]

Maybe they tried to hide their tracks by just using their zip code as a return address.

20500-0001

[muawiyah]

looks like a zip more appropriate to a firm than to a specific address ~ usps zip code site shows a different zip code for use by 'the white house' per se.

remember, zip codes cover areas, firm holdouts, box units, and specific buildings. when it comes to the federal government the zip is going to take that make to a sniffer operation near dulles airport ~ where they check it for bombs ~