Is it possible to use the ReadyPromise with a ModelGraphics? Ultimately, I am trying to set a model on an entity. This model needs to have some of its properties be of type TimeIntervalCollectionProperty. Therefor, I am using (new ModelGraphics()) to instantiate the model. However, I would like to draw a point or fallback billboard if the model fails to load, so I was hoping to have the ReadyPromise available, like it is in the standard "Model" object.
Is there any way to have both the properties implement the "Property" interface AND have the ReadyPromise callback when using models?