acf/update_field_group │ action-hook │ ACF 1.0

Usage

add_action( 'acf/update_field_group', 'wp_kama_acf_update_field_group_action' );

/**
 * Function for `acf/update_field_group` action-hook.
 * 
 * @param  $old_field_group 
 *
 * @return void
 */
function wp_kama_acf_update_field_group_action( $old_field_group ){
	// action...
}

$old_field_group

-

Where the hook is called

do_action( 'acf/update_field_group', $old_field_group );

do_action( 'acf/update_field_group', $new_field_group );

Where the hook is used in Advanced Custom Fields PRO

add_action( 'acf/update_field_group', array( $this, 'update_field_group' ) );