How to reload/ re render helper after view was re render at Ember

I have a view with a {{#each}} loop. The collection on which I do the iteration containing data that loaded as the app starts, and additional data that loaded later (only after success on an Ajax call).

When the additional data arrives, using promises I add the data to the array. I use Ember.MutableArray so I could change the array and refrash the view when I do so. However the view contains helpers inside the #each loop. And after the additional data rendered the helpers aren't executed again and I'm stack with the plain html

Part of my code:

// HTML
{{#each item in array}}
    <div>
        <!-- This Helper will be displayed for all items,
             except for the data from the Ajax call -->
        {{my-helper item.imgUrl}}
    </div>
{{/each}}

// JS
Ember.ObjectController.extend(
{
   init: function()
   {
        var ctrl = this;

        var data = ctrl.get('controllers.application.appData');

        ctrl.array = Ember.A(data.array);

        data.DataLoadedDefer.promise().then(function()
        {
             ctrl.array.unshiftObject(data.serverData);
        });
   }
});

So how can I reload the helper, or maybe refresh the whole view?