Me too, just noticed this in my error_log, once every day.
The error is the SQL lines 401-405 of “404-redirected/includes/functions.php”, reads:
401) //Find unused urls
402) $query = "select id from " . $wpdb->prefix . "wbz404_redirects where status = " . $wpdb->escape(WBZ404_AUTO) . " status ";
403) $query .= "timestamp <= " . $wpdb->escape($then) . " and id not in (";
404) $query .= "select redirect_id from " . $wpdb->prefix . "wbz404_logs";
405) $query .= ")";
that line 402 should read:
$query = "select id from " . $wpdb->prefix . "wbz404_redirects where status = " . $wpdb->escape(WBZ404_AUTO) . " AND ";