Substack change history: Post emails delayed

Substack reported a major incident starting 2025-10-20 13:41 UTC, delaying scheduled post emails and partially disrupting publication dashboards, subscriber tabs and statistics. The vendor linked scheduled-post delays to a service-provider outage; manual publishing was a workaround. Scheduled sends recovered and the backlog cleared; the incident resolved at 2025-10-21 00:52 UTC after 11 h 11 min.