I got that same email last weekend; but noticed it when my daughter was on her way home from shopping at Kohls on Sunday evening. (last day to use it). I called the store and asked if I could come in Monday with the receipt, and would they honor it. She said yes. So basically when I went back, she returned the items; then re-rang them and took the $10 off.
I don't know how it would work though, if you had not actually shopped there during those few days.