Events Calendar 3.9.3 // Change Organizer Slug

gistfile1.php

/**
 * Alter the organizer post type slug.
 *
 * Remmber that if rewrite-related properties (such as the post type slug) are
 * changed you may need to flush permalinks by visting the Permalink Settings
 * screen.
 */
function modify_organizer_type_properties( $properties ) {
	// Change the slug
	$properties['rewrite']['slug'] = 'custom_organizer_slug';

	return $properties;
}

// This hook is only available if Events Calendar PRO is activated
add_filter( 'tribe_events_register_organizer_type_args', 'modify_organizer_type_properties' );