Need guidance for DB migration for upgrade to GN 4.2.13

After a local test upgrade from 4.2.11 to GN 4.2.13, the logs WARN that a database migration may be required. We’re new-ish users to deploy GeoNetwork… Where is the guidance documentation for database migrations? From the log, it reads like this is to be done manually, or is it automagic? Logs also suggest that migration task is missing or misplaced? It suggests there are samples in WEB-INF/sql/migration, but after a find some are in WEB-INF/classes/setup/sql/migrate