Impacted during impact analysis and iteratively visits dependent and supporting classes making actual code updates [1].During the Incremental Change process, after the a code has been incorporated into the software system, the system may or may not become inconsistent. In order to return the system back to a consistent state, change propagation changes all classes in the former system that have become a source of inconsistencies. This activity is similar to impact analysis. Change propagation starts with the classes identified as Impacted during impact analysis and iteratively visits dependent and supporting classes making actual code updates [1].