The Realm Platform is powered by Realm Object Server which is the core product that powers both the Realm Cloud and self-hosted deployments. The Realm Object Server has a variety of backup methods for the realms contained on disk and these can be used to provide a snapshot of the state of the realms at a certain period of time. This snapshot can then be provided to or by the Realm Operations team to then build a new server with this data either in the cloud or self-hosted as part of a custom support plan.
If you are considering any sort of migration in the future we recommend that you build your app to account for a switch in the Realm Object Server hostname for the sync APIs, such as building in a remote config functionality. Additionally, you should also add a client reset callback so that you can be sure there is no data loss between when users last connected to your old ROS and when they connect to the new ROS.
Please contact [email protected] for more details.