When R. Keyserling is no longer the operator, the successor inherits control by receiving (1) the ARCHITECT_KEY in backend/.env, (2) the Cathedral signer passphrase, and (3) administrator access to the Architect Suite at /architect. No federation node needs to be reconfigured — the central brain remains intact. The successor's first act is POST /api/codex/keygen with a new passphrase, which rotates the Ed25519 keypair and stamps the ledger with their fingerprint.