The only thing I actually use is to compare HV Cell Voltage every few months. See my latest comparision.
Not sure. As you can see I have taken measurements for a couple years now. Not much change.I took a quick glance at your HVmax and HVmin cell data. The last data point shows >50 mV spread in the results. For comparison, my 2011 typically shows a spread of about 20 mV from max to min. I don’t recall seeing such a large voltage spread even with the degraded battery in my LEAF.