It looks like the yellow light on the HV display last night was an indication that something was wrong.

Channel u204 failed to ramp from Standby to Physics shortly after midnight.  The software only sends the new voltage request once.  If that communication failed, it would have left the yellow light on.

More worrying is the behavior shortly after 1:00 AM.  When the voltage was set back to the Standby level the software first turned this channel up to the Physics level before turning it down.  The ramp rate was very high.

Reccomendation:  The standby voltage should be lower than the physics voltage by more than a step size.  This assures that the rampup between these two levels proceedes in a couple of steps.

Software should do another check on the physics voltage setting before presuming that the rampup is done.