Management console is inaccessible during management cluster upgrade

During the management cluster upgrade, Keycloak may be unavailable for up to five minutes with the Keycloak alerts firing in StackLight. Consequently, web UIs such as MOSK management console, Prometheus, Alertmanager, Alerta, OpenSearch Dashboards, and Grafana for both management and MOSK clusters may be temporarily inaccessible. This behavior is expected, no action is required.