Shifting of SEP managed Clients from one Managed server to the other

hi all

we had a SEPM 11.0.6 on a server and all the clients (about 150 ) on it. now we have deployed SEPM 12.3 on a separate server and wanted to shift all the user to that new server. so is there a way to shift all the clients from one server to the other.? as all the SEP clients are of older version so is there a way to push and change the new clients on the old ones insted of manually uninstalling the old and reinstall the new one??