VST3 SDK question...

I posted this question in 2015, I’m still looking for an answer. The plugin in question is fully developed and functioning in the field, but there is one more feature I would like to add which requires an answer to the following:

The plugin I’m currently developing needs to know when the VST Host (in my case Cubase) STOPS (i.e., the stop button on the transport bar is clicked, or the equivalent). I can find no mention anywhere in the documentation that the host notifies the plugins of this event. Does anyone out there know if the VST Host notifies the plugins of this event, and if it does, how do I receive the message? A breakpoint on notify() in the controller and the processor is never tripped by Cubase transport start/stop.

Thanks in advance.