School Loop archives all published progress reports just before the beginning of the new school year. Because only published progress reports are archived and because changing gradebook dates can unpublish progress reports, it is a good idea to go back and republish all of your gradebooks for the year, beginning with the oldest and ending with the most current gradebook.
You can get to all of your gradebooks for each class from the Course Center. Open the gradebook and click the Publish button. Then on the assignment list click Publish again. No need to uncheck/recheck assignments.