In this lesson, Nick Palazzolo explores the concept of changing engagement types, such as switching from an audit to an agreed-upon procedure (AUP), a review, or an examination. He outlines legitimate and illegitimate reasons for changing the engagement and emphasizes that the report for the new engagement should not refer to procedures performed during the first engagement to avoid confusion. When transitioning from an audit to an AUP engagement, however, referencing the procedures performed during the audit is acceptable as both engagements involve referencing the procedures in their respective reports.