Well, I've made considerable progress, a copy of my spreadsheet is here, truncated to not retrieve live data (it just re-plots what is on sheet when you click refresh): https://drive.google.com/open?id=1yI...8PyCZ0c1cvdPgn

So I have the color bands. HOWEVER, there is still a bit of 'whitespace' at the two edges of chart. Also, I cannot seem to set the two x-axis to the same scale, e.g. starting at a half day, one takes only 'whole dates'.

The stacked area chart itself, seems to work but I think I'm still missing a few details. I welcome any help. Ideally, I'd like to set both x-axis to same scale, both y-axis to same scale, and hide the secondary axis. I had to include a second x-axis, as otherwise dates with data at two different times, plotted at the same horizontal position as I recall.

-Frank