waveform_calc_lags only works with 3 element arrays?

[leighton-watson]

For 4 element arrays there should be 6 different time lags; 1->2, 1->3, 1->4, 2->3, 2->4, 3->4. However, there are only 4 lags listed in the output csv file.
Input command: waveform_calc_lags mseed_all\* -i 227,231,234,240 -1 2022-10-06 -2 2022-10-07_00:00:00 -u 2 -o MCK1_227_231_234_240.csv -p 0.8
Output headers from csv file: t_mid mean_coef rms_.227. lag_.227._.231. r_.227._.231. rms_.231. lag_.231._.234. r_.231._.234. rms_.234. lag_.234._.240. r_.234._.240. rms_.240. lag_.240._.227. r_.240._.227. consistency

I can use a subset of the array with 3 elements. There are 3 time lags for this; 1->2, 1->3, 2->3. There are 3 lags listed in the output csv file.
Input command: waveform_calc_lags mseed_all\* -i 227,231,240 -1 2022-10-06 -2 2022-10-07_00:00:00 -u 2 -o MCK1_227_231_240.csv -p 0.8
Output headers from csv file: t_mid mean_coef rms_.227. lag_.227._.231. r_.227._.231. rms_.231. lag_.231._.240. r_.231._.240. rms_.240. lag_.240._.227. r_.240._.227. consistency

It seems like waveform_calc_lags works properly for 3 element arrays but gives strange results for 4 element arrays. I have not tested on arrays larger than 4.