Field allowed values override contains deletions, but not additions

I've a particular list(text) field with some default value options.

I've tried to override the allowed values with the following:

You can see here that the diff in the feature:

However, when I try to create a features_override for this field to capture these new allowed values, the export only contains the deletions, not the additions:

/**
 * @file
 * denver_cod_session.features_override.inc
 */

/**
 * Implementation of hook_default_features_overrides().
 */
function denver_cod_session_default_features_overrides() {
  $export = array();

  $features_override = new stdClass;
  $features_override->disabled = FALSE; /* Edit this to true to make a default features_override disabled initially */
  $features_override->api_version = 1;
  $features_override->name = 'denver_cod_session';
  $features_override->description = 'Denver specific tracks.';
  $features_override->component_type = 'field';
  $features_override->component_id = 'node-session-field_track';
  $features_override->value = array(
    'additions' => array(),
    'deletions' => array(
      0 => array(
        'keys' => array(
          0 => array(
            'type' => 'array',
            'key' => 'field_config',
          ),
          1 => array(
            'type' => 'array',
            'key' => 'settings',
          ),
          2 => array(
            'type' => 'array',
            'key' => 'allowed_values',
          ),
          3 => array(
            'type' => 'array',
            'key' => 'Track 1',
          ),
        ),
      ),
      1 => array(
        'keys' => array(
          0 => array(
            'type' => 'array',
            'key' => 'field_config',
          ),
          1 => array(
            'type' => 'array',
            'key' => 'settings',
          ),
          2 => array(
            'type' => 'array',
            'key' => 'allowed_values',
          ),
          3 => array(
            'type' => 'array',
            'key' => 'Track 2',
          ),
        ),
      ),
      2 => array(
        'keys' => array(
          0 => array(
            'type' => 'array',
            'key' => 'field_config',
          ),
          1 => array(
            'type' => 'array',
            'key' => 'settings',
          ),
          2 => array(
            'type' => 'array',
            'key' => 'allowed_values',
          ),
          3 => array(
            'type' => 'array',
            'key' => 'Track 3',
          ),
        ),
      ),
      3 => array(
        'keys' => array(
          0 => array(
            'type' => 'array',
            'key' => 'field_instance',
          ),
          1 => array(
            'type' => 'array',
            'key' => 'default_value',
          ),
        ),
      ),
    ),
  );
  $export['denver_cod_session'] = $features_override;

  return $export;
}