This is a pane of the Simpsons stamps (4399-4403) that has a date error/freak/oddity. The years on the far left side are missing the "2" of 2009. This in itself would classify it as a Freak, but I have 3 more copies with the same error, all purchased in three different post offices in two different states, and three of them have Homer on the back while one has Lisa. When I raised the question of what to call it with Linn's, I was told it was a "repetitive freak".
Anybody ever hear of that term?