Any one else get multiple forms mailed to your home?

I received two advanced notices on the same day that the form was
coming in the mail. Okay, I figure a waist of postage.

Then I get two exact forms in the mail. The same exact forms, not a
short one and a long one. Different bar codes on each envelope.

I spoke to the postal delivery person and she said that she asked the
same question at her office. Clues, beside the obvious?

--
"Well, it doesn't happen all the time, but when it happens, it happens
constantly."