Prior to our big 2017-2018 vent we had a cage servo engaged to keep SR3 pitch at a hand-set OSEM value.  We have not been using this cage servo in the runup to O3, and I wanted to confirm that we shouldn't need it any more.  (Obviously we've been doing okay without it.)

In the attached plot, I show both the oplev and OSEM monitors of SR3 as well as the temperature of the corner station (nice and constant!) and our BNS range (calibration not certified good for all times, so this is just a rough figure of merit).  I think that these show that SR3 isn't moving too much, and we shouldn't worry about it too much.  In particular, we used to servo only pitch, since the concern was with wire heating, and pitch is even more constant than yaw.