We have serveral environments managed on the bloomreach cloud.
I have deployed our upgraded distribution to one with no issue, however I am see the following stack trace when deploying to another environment:
[org.apache.catalina.core.StandardContext listenerStart] SEVERE Error configuring application listener of class [org.hippoecm.frontend.plugins.login.ConcurrentLoginListener] java.lang.UnsupportedClassVersionError: org/hippoecm/frontend/plugins/login/ConcurrentLoginListener has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0 (unable to load class [org.hippoecm.frontend.plugins.login.ConcurrentLoginListener])
This suggests to me that this environment is running Java 8. I tried deleting the environment and starting from scratch - but the same issue persists.