The registration itself it not persisted.
What is persisted is which job belongs to which deployment. This together with the registrations at runtime allow the job executor to decide for which jobs to poll.
If I understand you correctly, you have different process applications deployed in these containers. In this case, registrations are automatically made whenever you start the container. In effect, each job executor will pick up only those jobs that belong to the deployments for which there are process applications deployed on their respective container.
Cheers,
Thorben