Moving event between ressource in the unit view

I have a problem when moving an event from a ressource to another ressource in the unit view.
I do some check in the beforeDrag and beforeEventChanged, but both event return true.
With the debugger I have checked the property used for the unit view (ressource).
It has the value of the ressource that is displayed.
The fact is that this event disappear from the scheduler, if I check the _rendered property before and after moving, I have 1 event less after the moving.
The event is correctly moved in my database, as when I reload the entire page I have my event that display normally. (If if check the event in scheduler._event, I have the same datas)
I don’t have any problem when I move the event inside the same ressource.
Having modified the ressource property, I wonder if anything else must be modified so it is rendered correctly after the update (as long as I am in the OnBeforeEventchanged, I can see that my event is displayed correctly)