Starting with Skype for Business Cloud Connector (Cloud Connector) 1.4.1, we introduced an automated update process: Cloud Connector automatically updates based on the update schedule that administrators have configured for their Cloud Connector Hybrid PSTN Sites.
Auto update handles both Cloud Connector Edition updates, and Windows operating system updates for all Cloud Connector virtual machines and the host appliance.
For details on understanding how auto updates work with Cloud Connector, please our Microsoft Tech Community blog: Understanding Cloud Connector Edition Auto Update.