Forgot to add this comment last week, my apologies.  The PMC Refl rise appears to coincide with a temperature change in the enclosure and LVEA.  Seen on the Weekly Environment plots, there is a clear downward change in all 4 temperature sensors in the PSL enclosure Laser Room (TBLN, TBLS, ACN, ACS), and a clear drop and levelling out of the temperature in the enclosure Anteroom and the PSL LVEA sensor (sits on the exterior PSL enclosure wall between the enclosure and HAM1).  This is also seen on a couple of items exposed to ambient temperatures, namely the NPRO laser pump diodes (in the NPRO laser head in the enclosure Laser Room) and the LVEA Control Box (in the PSL rack outside of the enclosure).  On the Weekly Cooling set of plots, a clear change in these 3 channels (*_NPRO_LD[1/2]TEMP, *_CB1_TEMP) is seen coincident with the temperature change witnessed by the various PSL temperature sensors.

Seeing this, we attempted a brief alignment tweak of the PMC beam from the Control Room (theory being that since the change in PMC Refl coincides with a temperature change, maybe an temperature-induced alignment shift caused the increase in PMC Refl).  Unfortunately we saw no change in PMC Trans with an alignment tweak.