Mississippi holds its presidential primary on March 8. Willie Wilson petitioned to get on the ballot, and met the 500-signature requirement. The Democratic Party at first thought the petition needed 100 signatures in each of the old five U.S. House district, so they did not certify his name to the Secretary of State. Then the party became aware that there is no distribution requirement in effect, but by then some ballots had already been printed and mailed to overseas absentee ballots.
On February 10, the Mississippi Supreme Court heard arguments on whether the mistake should be corrected. The Secretary of State argues that because some overseas absentee voters received a ballot without Wilson’s name, therefore it is impossible to correct the mistake. But the U.S. Supreme Court came to a contrary decision in Norman v Reed in 1992. It ordered Cook County general election ballots reprinted only thirteen days before the general election, because the Harold Washington Party nominees for Cook County office had been wrongfully left off the ballot. Many thousands of Cook County absentee ballots had already been cast at that point. There are other examples as well. See this story.