Content Servers are no longer fully interoperable with clients that use a release 1901 or earlier. In particular, the PropertyService is only accessible by more modern clients. This means that a new Master Live Server cannot be accessed by a Content Management Server or a Replication Live Server from release 1901 or earlier.

While interoperability between different releases on the network layer is not guaranteed, in this particular case an incompatibility is known and mixing releases is not possible.

(CMS-13991)