Hello License Developer,
Thank you for writing.
currently supports notifications only when a node is being selected. We are planning to provide a way to tell when a node is being unselected.
At the moment, I cannot give you a specific timeframe. For now, you could try keeping track of selected nodes and determine when a node gets unselected.
Please let us know whether this functionality is critical to your project at this point. If this is the case, we will increase the priority of this feature.
If you have any additional questions, please contact me.
the Telerik team