The upgrade of the RESTBase Cassandra cluster is complete (a rollback should no longer be necessary), the internal APT repository should be updated so that the cassandra311 component contains 3.11.2.
http://dl.bintray.com/apache/cassandra/pool/main/c/cassandra/cassandra-tools_3.11.2_all.deb
http://dl.bintray.com/apache/cassandra/pool/main/c/cassandra/cassandra_3.11.2_all.deb
http://dl.bintray.com/apache/cassandra/pool/main/c/cassandra/cassandra_3.11.2.diff.gz
http://dl.bintray.com/apache/cassandra/pool/main/c/cassandra/cassandra_3.11.2.dsc
http://dl.bintray.com/apache/cassandra/pool/main/c/cassandra/cassandra_3.11.2.orig.tar.gz