When the new SSH remote host is added in Jenkins Configuration, and the changes were applied, from the list of 10 hosts (11th should be added) only 3 of them left in configuration. Then when the backup copy of org.jvnet.hudson.plugins.SSHBuildWrapper.xml file were loaded or the "reload configuration from the disc" option were used we still saw only 3 hosts instead of 10. After restart Jenkins with backup file loaded in configuration the initial list of 10 hosts occure.