code: private void fillMissingDurations() {
          long[] extendedArray = new long[buildNumbers.length];
          Arrays.fill(extendedArray, -1);
          System.arraycopy(durations, 0, extendedArray, buildNumbers.length - durations.length, durations.length);
          durations = extendedArray;
      }
docs: Since durations were added later there is need to fill missing data for those statuses.