The following bug fix is included in this release:
Fixes broken support for cross-cluster search (CCS). When you upgrade Elastic Cloud Enterprise from 2.0.0 and later to 2.2.1, CCS is now supported. Before, Elastic Cloud Enterprise was unable to support CCS capabilities if you upgraded from 2.0.0 and later to 2.2.0.
Release date: April 17, 2019