Readiness partitioning happens before upload
Every export run splits inbox rows into ready and blocked sets. Blocked rows are marked failed with a readiness failure type and an operator-actionable, redacted message — they are never sent to EmailBison as broken accounts that later fail authentication inside a campaign.
- Readiness covers inbox lifecycle status, DNS and MX state, MTA assignment, and credential integrity.
- Launch gates are checked at job creation and again before each upload batch, failing closed when state is unknown.
- Ready rows decrypt credentials only at upload time; blocked rows never touch provider APIs.
Uploads are paced and retried deliberately
Export processing batches uploads with spacing between batches and retries transient provider failures with backoff. Authentication and validation errors are treated as non-retryable so a bad key or rejected payload fails fast instead of hammering the provider.
Pair exports with EmailBison MX diagnostics
EmailBison is the one supported sequencer with provider-backed MX validation, which helps diagnose provider-facing mailbox issues after export. MX checks complement SMTP readiness — they do not replace launch gates or seed-placement evidence for first prospect traffic.