Subscription for data changes in OPC UA server [IoT Gateway]

IoT Gateway documentation states that only certain nodes on the server support subscriptions for data changes, and all of those nodes are in the ABB information model. But what about the nodes inside "DeviceSet", which follow the OPC UA Robotics Companion Specification? When I use a client application to subscribe to the "ActualPosition" node, for example, the server does not notify about any data changes.