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Goals

<!--- What are you trying to achieve? -->
In my app, syncing to a server is a 'premium' feature. essentially, users can create a local realm database to store app data but backing up requires a subscription. because of this, whether a realm should be synced or not can change at any time. I've seen the docs on migrating a local realm to a synced one, but it seems like it will add a lot of complexity to go back and forth. is there a simple way to, for example, set up a synced realm but not give it a sync address? or would this involve connecting to a custom auth server of some sort and checking if the user has a subscription, then syncing manually?

• Realm JS SDK Version: 1.13.0
• Node or React Native: React Native
• Client OS & Version: n/a
• Which debugger for React Native: None