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+# Mastodon data cutover
+
+The Argo `mastodon` application uses the maintained upstream chart at the version pinned in `bootstrap/mastodon.yaml`. Its PostgreSQL host is the independently managed `mastodon-postgresql` CloudNativePG cluster. The existing Valkey instance and Secret references were preserved.
+
+On 2026-10-22, the old PostgreSQL database was quiesced and dumped in custom format, restored into CloudNativePG, and checked by account count (5,651 at cutover), application-role privileges, all three ready application Deployments, and the public site and WebFinger responses. The old `postgresql` StatefulSet was then scaled to zero. Its `data-postgresql-0` PVC (UID `9f85687c-1bde-407b-ae94-c5acfc0f5084`) and PV remain for rollback. The old Valkey PVC (UID `d3213987-e8eb-4fa9-8257-0613138920ad`) is still live.
+
+Do not delete the old database PVC or its final dump until an independently verified backup and retention decision exist. A rollback after new writes to CloudNativePG needs a fresh database export or another data-reconciliation plan; simply starting the old PostgreSQL pod would lose new activity. The pre-migration local installer in `fediverse/` is retired and must not be used to update this release.