The Move to History is an event that occurs at the end of every Iteration. The process is simple:

  1. Everything that is in your Current iteration is sent to History in the Last iteration.
  2. Everything what was not completed is kept in the new Current iteration.
  3. Everything that was in Next, is brought to Current.
  4. Everything that was in Next+n, is brough to Next+(n-1).

You can move an iteration to history at any time from the Action menu.

1. Select "Actions" from the left navigation menu
2, Click "Move to History"

For more information, see the article Next Iteration Planning.