* @since 7.1.0 Added the `$format` parameter.
		 *
		 * @param string     $date   The formatted start date for the order.
		 * @param LLMS_Order $order  The order object.
		 * @param string     $format The requested format of the date.
		 */
		return apply_filters( 'llms_order_get_start_date', $date, $this, $format );
	}

	/**
	 * Retrieves the user action required when changing the order's payment source.
	 *
	 * @since 7.0.0
	 *
	 * @return null|string Returns `switch` when the payment source can be switched and `pay` when payment on the new source
	 *                     is required before switching. A `null` return indicates that the order's payment source cannot be switched.
	 */
	public function get_switch_source_action() {