The attached PNG shows the pressure graph from the SH overview display. Note the several days near the end of the record where the day shows as a solid bar of one color. That's the bug.
All of the other overview graphs look fine, and the detail pressure waveforms on these incorrectly displayed days look fine as well.
Exiting and restarting SH will result in a slightly different set of days shown incorrectly.
I can supply a backup of my SD card with these days on it if that's helpful - and the request is made reasonably soon.
I have tried rebuilding the SH data from the SD backups - that didn't help.