Well, wouldn't the scene object be destroyed so the object's post event would also be destroyed.
I would create a User AI say PlatformsAI instead of an Object AI to maybe setup/control/destroy Platforms and then send them events of what to do and how to initialize or end them. Then when you are going to destroy a scene, stop/destroy those platforms inside your PlatformsAI onDestroy Event or something. Or even save their variables in PlatformsAI table or hashtable of some sort. Then respond with a success, make the new scene and send that PlatformsAI a onRestart post event once its created.
Hope that helps.