The preview shows wrong lto date, because of wrong initialization.
In uc_lto_nodeapi 'view' change $expiration to $node->expiration
From

      case 'view':

        $query = db_query("SELECT * FROM {uc_lto} WHERE nid = '%d'", $node->nid);
        $result = db_fetch_object($query);

        if ($result != FALSE) {
          $expiration = $result->expiration;
          $node->lto_type = $result->type;

to

      case 'view':

        $query = db_query("SELECT * FROM {uc_lto} WHERE nid = '%d'", $node->nid);
        $result = db_fetch_object($query);

        if ($result != FALSE) {
          $node->expiration = $result->expiration;
          $node->lto_type = $result->type;