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Hi I have an app that runs on iOS and MacOS (actually they are separate apps) and Core Data from a NSPersistentContainer, is synced with iCloud using a custom solution utilising pre-NSPersistentCloudKitContainer CloudKit methods. I would like to migrate that solution to NSPersistentCloudKitContainer but am having trouble figuring out how to do it and whether it's even possible. In particular, as I cannot guarantee that all devices would migrate at the same time, there would need to be a period where both synchronisation methods are active. Moreover, they would need to be active on one device, which would need to act as some sort of translator between the two methods. Then, it would be quite hard to determine when to stop using and delete old records from the cloud as that would have to be done from the last device to migrate. And that would be quite hard to determine from the app. Finally, as each device has its own Core Data objectIDs all managed objects would end up being duplicated in iCloud. Now that could be fixed with some code that checks for duplicates but maybe not without user noticing it. Has anyone maybe attempted something like this? Do you think it's doable or is it better to create a new app and then try to migrate using app groups or something like that. Thanks a lot!