WHERE Clause in nested json data Laravel 5

As a follow up question in my last post, I just can't figure out how to use WHERE clause when you have a nested json data. Please see my last post as reference to this.

So, I have this kind of data generated by using relationship in my models:

[
  {
     "id":1,
     "name":"South Luzon",
     "branches":[
        {
           "id":1,
           "machinenum":108,
           "name":"Alaminos",
           "region_id":1,
           "user":{
              "id":52,
              "name":"",
              "email":"baic@alaminosbranch.addessacorp",
              "role":0,
              "machinenum":108,
              "created_at":"2016-07-11 05:58:04",
              "updated_at":"2016-07-14 09:49:00",
              "pendings":[
                 {
                    "id":10,
                    "user_id":52,
                    "region":"South Luzon",
                    "branch":"Alaminos",
                    "docdate":"2016-07-14 00:00:00",
                    "ls_or":12345,
                    "por":1,
                    "ls_ci":12345,
                    "ci":2,
                    "ls_ch":12345,
                    "ch":2,
                    "dep":5,
                    "cla":0,
                    "grpo":3,
                    "si":25,
                    "so":62,
                    "sts":2,
                    "disb":3,
                    "arcm":5,
                    "apcm":65,
                    "pint":2,
                    "rc_cash":1,
                    "reason":"Test Reason Alaminos",
                    "created_at":"2016-07-14 09:48:55",
                    "updated_at":"2016-07-14 09:48:55"
                 }
              ]
           }
        }

What I'm trying to do is loop all regions with branches and get the pending of each branches. I'm successfully done the looping with my last SO question. Now, I just want to filter the date when the pending was created.

I'm trying to do this:

$regions = Region::with(array('branches->user->pendings' => function($query) {
    $query->where('created_at', '=', '2016-07-14 09:48:55');
}))->get();

But I'm getting this error:

BadMethodCallException in Builder.php line 2345:
Call to undefined method Illuminate\Database\Query\Builder::branches->user->pendings()

I've also done some research but end up asking here. Thanks in advance and please don't forget to see my last SO question as your reference.

via Chebli Mohamed