gistfile1.txt

add_action( 'pre_get_posts', 'exclude_events_category' );
function exclude_events_category( $query ) {
  if ( $query->query_vars['post_type'] == TribeEvents::POSTTYPE && $query->query_vars['eventDisplay'] == 'month' && !is_tax(TribeEvents::TAXONOMY) && empty( $query->query_vars['suppress_filters'] ) ) {
    $query->set( 'tax_query', array(
      array(
        'taxonomy' => TribeEvents::TAXONOMY,
        'field' => 'id',
        'terms' => 49,
        'operator' => 'NOT IN'
      )
    ) );
  }
  return $query;
}