Major incident

Piano Software: Composer waterfall issues on US environment.

Affected: Composer Experience Execution - US

Current status of Piano Software: Operational — live Piano Software status

Timeline

1. Apr 27, 2026, 16:57 UTC
   investigating
   We have found an issue with our priority rules for API interaction on server/edge in Composer. The dev team is currently investigating. Clients may find their list order being changed or unsorted without any user interaction. We will continue updating this incident once we identify the root cause.
2. Apr 27, 2026, 18:37 UTC
   investigating
   Our team has restored the priority rules to their pre-incident state while we continue to investigate the root cause. We advise customers to avoid making changes to priority rules until the investigation is complete. We will provide further updates as more information becomes available.
3. Apr 27, 2026, 22:01 UTC
   monitoring
   The issue has been identified and mitigated; we will continue monitoring the remediation.
4. Apr 28, 2026, 09:20 UTC
   resolved
   This incident has been resolved.
5. Apr 28, 2026, 14:04 UTC
   postmortem
   RCA report for the incident is available at [**this link**](https://docs.piano.io/wp-content/uploads/2026/04/2025-05-06-RCA-Experience-Priority-Data-Incident.pdf).

Updates as published by Piano Software (original).