Extend / Override Schema.org JSON_LD Output https://schema.press/docs/extend-schema-output/

schema-wp-extend-output.php

<?php //* do not include php tag

add_filter('schema_output', 'schema_wp_extend_output_987345256');
/**
 * Extend / Override Schema Output
 *
 * @since 1.0
 */
function schema_wp_extend_output_987345256( $schema ) {
	
	global $post;
	
	if ( empty($schema) ) return;
	
	// Debug
	// echo '<pre>'; print_r($schema); echo '</pre>';
	
	// Modify NewType to present the actual schema.org type
	if ( $schema['@type'] != 'NewType' ) return $schema; 
	
	// Modify / Override values
	$schema['title'] = 'New Title';
	
	// Add new values
	$schema['name']			= 'Event Name';
	$schema['startDate'] 	= '2016-07-10T06:00';
	
	// Unset extras
	unset($schema['headline']);
	unset($schema['author']);
	unset($schema['publisher']);
	unset($schema['ArticleSection']);
	
	return $schema;
}