Hi, not sure if this is intended but it makes the undo feature lose a lot of its usefulness.
If this happens to be intended it would be great to complete the feature properly in a future update 
Here it goes :
- Create empty track and insert plugin (either stock or third party)
- Arm Write automation, play, write automation on a plugin setting then hit stop, deactivate write, keep read active
- Unload plugin from the insert
- Undo from MixConsole top left corner
- Plugin is back as insert but all the the automation data is gone
Cubase Pro 9.0.10
Windows 10