public function save_attendee_info() {
		if (
			! isset( $_POST['nonce'] )
			|| ! wp_verify_nonce( $_POST['nonce'], 'save_attendee_info' )
		) {
			wp_send_json_error( null, 403 );
		}

		if ( empty( $_POST['event_id'] ) ) {
			wp_send_json_error( null, 400 );
		}

		/*
		 * There are hooks on wp_loaded (See various process_front_end_tickets_form methods) that handle saving of the
		 * ticket meta from $_POST by Tribe__Tickets_Plus__Meta__Storage::maybe_set_attendee_meta_cookie.
		 */

		/**
		 * Get all tickets currently in the cart.
		 *
		 * @since 4.9
		 *
		 * @param array $tickets Array indexed by ticket id with quantity as the value
		 *
		 * @return array
		 */
		$tickets_in_cart = apply_filters( 'tribe_tickets_tickets_in_cart', array() );
		$meta_up_to_date = tribe( 'tickets-plus.meta.contents' )->is_stored_meta_up_to_date( $tickets_in_cart );

		wp_send_json_success( array(
			'meta_up_to_date' => $meta_up_to_date,
		) );
	}