No actually the plugin is kind of not updated. It’s using old format or I guess it’s not using. Try using the rich snippet tool and see it for yourself. Variables vote and count are not used at all for some reason…
remove/comment line 736:
'<abbr title="' . $this->iso8601(strtotime($review->date_time)) . '" class="dtreviewed">' . date("M d, Y", strtotime($review->date_time)) . '</abbr> ' .