Since optical gain was changed from August and it changes the optimal offset for BPC, I changed it.
Figure 1 shows the BPC yaw error signals when turning on BPC with DC readout.
Old offset value was 0.097 but it seemed to large, so I reduced it to 0.9 (K1:BPC-YAW_ETMY_INF_OFFSET).

Note:

This osffset was the one reported in klog33989 and temporally solved by adding offsets as reported in klog34021.
We have no idea on the reason why the offsets appear, so it should be investigated later.