ember-data model is not being deleted when transitioning a route

I need to delete a model when I leaving a route. I am using the following in the route:

actions : {
    willTransition: function(transition){
        //Cleanup search model
        var model = this.modelFor('route1.index');
        model.deleteRecord();
        //At this point the model.get('isDeleted') = true
    }
}

From ember inspector when I have transitioned to my new route route1.route2, I can still see the model and its isDeleted property is now false.

Why is this not working?