If you previously taught a course using Perusall, you can easily migrate your content to a new course, while preserving student work in the old course for archival purposes.
If you have integrated Perusall with your learning management system, create a new course through your LMS and then launch Perusall from the new course, which will create a corresponding course in Perusall that is linked to the new course in the LMS. Now, in the new Perusall course, navigate to Course Setup > Readings > Documents > Add > Material from another course and copy over your documents and assignments to the new course. All you'll need to do now is to adjust the assignment due dates.
If you are using Perusall standalone, click the Perusall logo to go back to the My Courses page, and then click Copy Course. This will create a copy of your old course, copying over documents and assignments but not the roster or student data.