I have pushed my notebook branch to master on https://github.com/lsst-dm/OPS_Rehearsal_2
As for the plot labels, "old" refers to the original processing run where the wrong biases were being applied and "new" refers to the updated processing run which used the correct biases. This could be noted in the captions, e.g.:
Figure 2: Left: Night 2 dark with incorrect (i.e. "old") bias subtracted. Right: Night 2 dark with correct (i.e. "new") bias subtracted.
Or, if preferred, I could provide updated versions with any title you suggest (and, of course, if you'd rather the titles be left off entirely, that can easily be done with cropping).