yeah, that was my point about the calibration sequence.... maybe will post in the JJ FB group.
I tend to run the calibration sequence on my JJ twice. I do get 1-2 mV higher calibration values with the second run. Thus a single calibration run doesn't seem to produce over 99% O2 environment long enough. It is very consistent anyway.
All my cells have behaved identical, and waiting for replacement. At 12 months all three still calibrate to 50,51 and 50 mV. JJ-CCR cells from Oct 2018.
I would ditch any cells waking-up during dive or showing any other erratic behaviour.