Thank you John, unfortunately its not working.
The custom tax is called ‘area’ which has two categories within.
When try your code with ‘area’ put in ‘your-taxonomy-slug’ i get a fatal error and the admin page doesn’t load completely..
Fatal error: Call to undefined function get_post_terms() in functions/inc/acf.php on line 71
Line 71 is..
$terms = get_post_terms($post->ID, 'area', $args);
