Migratetorocky in an airgapped environment

The documentation for migratetorocky seems to indicate the system being migrated requires access to the internet for downloading packages. If that’s true, it’s problematic in the airgapped environment in which I live. We live via downloaded local repos that are refreshed on a periodic basis. Will that environment work with migratetorocky? If not, it puts us in a difficult position to migrate hundreds of production systems off of CentOS.