The Executions tab always shows timestamps in UTC by design, and the UI does not convert them to the workflow or system timezone. The Schedule Trigger itself respects the timezone configured at the workflow level, as long as the workflow is republished after any change.
Once that is correctly set, the documentation does not describe any n8n-side reason for a consistent one-hour offset. In practice, this usually points to daylight saving time (DST) or the host/container timezone configuration rather than an issue with n8n itself.