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Perhaps I misunderstood, but I believe I was told that I would have the ability to migrate existing code, which currently uses a public database from using a naive fetch with a date check, to using change tokens. However, after launching the sample app on a public database, it appears that it's still not possible to create custom zones in a public database, which is required for change tokens and notifications. Did I misunderstand the conversation, or is there a secret way to do this now? Any help is much appreciated. If it's not possible, is it worth filing a feedback request for this feature?