BP new Event Dispatcher cannot be deleted after modification

Changing the variable type of an Event Dispatcher in the Blueprint editor results in an impossible to compile situation. The BP must be then recreated due to being unable to remove the unattached event dispatcher.

1. Create a new Blueprint
2. Open the Blueprint and create an Event Dispatcher
3. Highlight the new Event Dispatcher and change its variable type to Integer
4. Attempt to compile the Blueprint
5. Delete the Event Dispatcher variable 

Result: A warning appears when attempting to compile that persists even after deleting the Event Dispatcher

Expected: The warning should be removed when the Event Dispatcher is completely removed from the Blueprint or Event Dispatchers should not be able to have their variable type changed.