WC3.2.1 debug.log notices

[20-Oct-2017 12:41:21 UTC] post_author was called incorrectly. Order properties should not be accessed directly. Backtrace: do_action(‘wp_ajax_bs_ship_track_email’), WP_Hook->do_action, WP_Hook->apply_filters, BS_Shipment_Tracking->send_tracking_email, BST_Tracking_Order_Email->trigger, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.
[20-Oct-2017 12:41:21 UTC] billing_email was called incorrectly. Order properties should not be accessed directly. Backtrace: do_action(‘wp_ajax_bs_ship_track_email’), WP_Hook->do_action, WP_Hook->apply_filters, BS_Shipment_Tracking->send_tracking_email, BST_Tracking_Order_Email->trigger, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.
[20-Oct-2017 12:41:21 UTC] order_date was called incorrectly. Order properties should not be accessed directly. Backtrace: do_action(‘wp_ajax_bs_ship_track_email’), WP_Hook->do_action, WP_Hook->apply_filters, BS_Shipment_Tracking->send_tracking_email, BST_Tracking_Order_Email->trigger, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.
[20-Oct-2017 12:41:21 UTC] id was called incorrectly. Order properties should not be accessed directly. Backtrace: do_action(‘wp_ajax_bs_ship_track_email’), WP_Hook->do_action, WP_Hook->apply_filters, BS_Shipment_Tracking->send_tracking_email, BST_Tracking_Order_Email->trigger, WC_Email->get_content, BST_Tracking_Order_Email->get_content_html, wc_get_template_html, wc_get_template, include(‘/plugins/blazing-woocommerce-shipment-tracking/templates/emails/bst-shipment-tracking.php’), do_action(‘woocommerce_email_order_details’), WP_Hook->do_action, WP_Hook->apply_filters, WC_Emails->order_details, wc_get_template, include(‘/plugins/woocommerce/templates/emails/email-order-details.php’), do_action(‘woocommerce_email_before_order_table’), WP_Hook->do_action, WP_Hook->apply_filters, BS_Shipment_Tracking->email_display, WC_Abstract_Legacy_Order->__get, wc_doing_it_wrong. This message was added in version 3.0.