pgmb_change_save_post_priority.php

<?php
/**

  Function to change the order of the save_post execution. Change the $priority value to change the priority
  lower numbers mean earlier execution. 

**/


function pgmb_change_autopost_priority(){
	global $post_to_google_my_business_plugin;
	
	$priority = 20; //Lower numbers get executed earlier, default is 10
	
	// -- Do not edit after this
	
	//Make sure the snippet doesn't crash the site if the plugin is disabled or the name of the variable is changed
	if(!isset($post_to_google_my_business_plugin) || !$post_to_google_my_business_plugin instanceof MBP_Plugin){
		return;
	}
	
	$reflection =  new ReflectionObject($post_to_google_my_business_plugin);
	try{
		//Make sure the metabox property actually exists
		$metabox = $reflection->getProperty('metabox');
	} catch (ReflectionException $ex) {
		return;
	}
	
	$metabox->setAccessible(true);
	$instance = $metabox->getValue($post_to_google_my_business_plugin);
	
	remove_action('save_post', [$instance, 'save_autopost_template']);
	add_action('save_post', [$instance, 'save_autopost_template'], $priority, 3);
}

add_action( 'after_setup_theme', 'pgmb_change_autopost_priority', 11 );