code: public Version cutoff(int index) {
          if (!isBeyondBounds(index)) {
              labels = labels.subList(--index, labels.size());
              numbers = numbers.subList(index, numbers.size());
          }
          return this;
      }
docs: Removes version numbers starting after specified index.
  
  @param index last number index (positive).
  @return version descriptor.
  @throws IllegalArgumentException if specified index is illegal.
  
  @since v1.1.0