Dynamically change views entity reference filter based on current form value
Here's my solution:

I used Entity Reference Prepopulate for my "venue" for my case (linked from my question), so whenever I choose a venue it will pass a parameter to the url.

Then I used Views Contextual Filter Query to get the value of the parameter from the URL and automatically filter the view without saving the form.

BTW, Entity Reference Prepopulate doesn't work on edit form, so you need to create a node_load function on your custom module. Check this for code reference

Then I created a code for edit link that has the param of venue and it's target id.

&lt;?php 
    $nid = arg(1);
     $node=menu_get_object(); 

    $l = l( t('EDIT'), 'node/'.$nid.'/edit',   array('query' =&gt; array('field_product_venue' =&gt; $node-&gt;field_product_venue['und'][0]['target_id'] )  ));
    echo $l; 


?>

I hope this will of help to somebody!

Thanks!