Obtenha o pedido postal por meta valor int

$defaults = array(
  	'numberposts'      => -1,
	'post_type'        => 'agent_listing',
  	'meta_key'	       => 'oepl_order_no',
  	'orderby'          => 'meta_value_num',
  	'order'            => 'ASC',
  	'suppress_filters' => false
);

'orderby' => 'meta_value_num', // for int field
'orderby' => 'meta_value', // text field
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