From this release, ExternalDNS can become aware of the records it is managing (enabled via `--registry=txt`), therefore ExternalDNS can safely manage non-empty hosted zones. We strongly encourage you to use `v0.5` (or greater) with `--registry=txt` enabled and `--txt-owner-id` set to a unique value that doesn't change for the lifetime of your cluster. You might also want to run ExternalDNS in a dry run mode (`--dry-run` flag) to see the changes to be submitted to your DNS Provider API.