When i was migrating database from version DSpace 4.2 to DSpace 5.3 migration task not end, when FlyWay could not insert data to metadata registry. Then it broke our database with eperson metada. Problem with creating was our mistake (.nextval was on existing id). But i think that, migration task should end when was problem in before migration method, not to continue, tell that all was ok and not only print error to log. It should stop a print error to outpu and do rollback.