It looks like v 1.7 RC 2 also fixed the issue.
[31-Jul-2017 19:54:16 UTC] id was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), do_action(‘template_redirect’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::do_wc_ajax, do_action(‘wc_ajax_get_refreshed_fragments’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::get_refreshed_fragments, woocommerce_mini_cart, wc_get_template, include(‘/themes/versatek/woocommerce/cart/mini-cart.php’), apply_filters(‘woocommerce_cart_item_product’), WP_Hook->apply_filters, call_user_func_array, gtm4wp_woocommerce_cart_item_product_filter, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong. This message was added in version 3.0.
[31-Jul-2017 19:54:16 UTC] post was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), do_action(‘template_redirect’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::do_wc_ajax, do_action(‘wc_ajax_get_refreshed_fragments’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::get_refreshed_fragments, woocommerce_mini_cart, wc_get_template, include(‘/themes/versatek/woocommerce/cart/mini-cart.php’), apply_filters(‘woocommerce_cart_item_product’), WP_Hook->apply_filters, call_user_func_array, gtm4wp_woocommerce_cart_item_product_filter, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong. This message was added in version 3.0.
[31-Jul-2017 19:54:16 UTC] product_type was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), do_action(‘template_redirect’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::do_wc_ajax, do_action(‘wc_ajax_get_refreshed_fragments’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::get_refreshed_fragments, woocommerce_mini_cart, wc_get_template, include(‘/themes/versatek/woocommerce/cart/mini-cart.php’), apply_filters(‘woocommerce_cart_item_product’), WP_Hook->apply_filters, call_user_func_array, gtm4wp_woocommerce_cart_item_product_filter, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong. This message was added in version 3.0.
[31-Jul-2017 19:54:16 UTC] id was called incorrectly. Product properties should not be accessed directly. Backtrace: require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), do_action(‘template_redirect’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::do_wc_ajax, do_action(‘wc_ajax_get_refreshed_fragments’), WP_Hook->do_action, WP_Hook->apply_filters, call_user_func_array, WC_AJAX::get_refreshed_fragments, woocommerce_mini_cart, wc_get_template, include(‘/themes/versatek/woocommerce/cart/mini-cart.php’), apply_filters(‘woocommerce_cart_item_product’), WP_Hook->apply_filters, call_user_func_array, gtm4wp_woocommerce_cart_item_product_filter, WC_Abstract_Legacy_Product->__get, wc_doing_it_wrong. This message was added in version 3.0.