SpiceDB schema rollback safety after new relationship writes

SpiceDB applies a new schema by replacing the active schema without retaining versioned history, and validates all new relationships against the current schema at write time.

After switching to a schema that removes a relation, existing tuples may reference deleted definitions, potentially causing permission check errors or being ignored, and the effect varies by backend such as PostgreSQL or CockroachDB.

Can a live system revert the schema safely after new relationships are written without downtime? Does rollback automatically resolve stale tuples across different datastores? What verification steps confirm safe rollback without manual tuple migration?