| Change Control Event | The purpose of the Change is to upgrade ACH Cisco CUCM Server from version 11.5 to 12.5 | Change Control Event | The purpose of the Change is to upgrade ACH Cisco CUCM Server from version 11.5 to 12.5CHG0069538 2023-03-18 08:00:00 – 2023-03-18 23:00:00The purpose of the Change is to upgrade ACH Cisco CUCM Server from version 11.5 to 12.5