You can upgrade your management node to the version 11.5 management node after you have successfully upgraded your 10.x version to version 11.0 and later. The vCenter Plug-in 4.3 requires management node 11.3 or later.
Upgrading the management node to version 11.5 from version 11.3
Upgrading the management node to version 11.5 from version 11.0 or 11.1