Mayoff Day 2001 in Richardson provided exhibits, and souvenirs, honoring the earliest known Mayoff
See the lyrics, watch and listen to the singing of the 2001 Mayoff Day song: Another Mayoff Day
The Invitation Envelope – A collector’s treasure? – What Happened?
Theory 1:
It is observered that even the United States Postal Service recognized the significance of Mayoff Day by deciding that it was more important to keep the envelope as pristine as possible, than it was to desecrate the upper right corner of the envelope with a cancellation mark.
Theory 2:
Another theory circulating anonymously within the USPS, is that the USPS recognizes that the stamp was supposed to say Cinco de Mayoff, but to make amends for omitting the ff they decided not to amplify their oversight by cancelling the stamp with a simple postmark. Instead they’ve cancelled the entire series of stamps as they are no longer available. In fact the very last ones were used on the 2001 Mayoff Day Texas invitations.
Theory 3:
There is one additional theory, and that is that rolling power blackouts fortuitously hit the USPS as it was about to mar a California bound envelope. As fate would have it, the stamps remain uncancelled and suitable for reuse. This should enable a California family to pay another 34 cents towards one whole kilowatt of their escalating utility bills.
Oliver Stone may produce a movie that explores all of the various theories.