I changed the demod for the PDH at end y over to the second channel in the same chassis. For this I had to change an SMA cable, so the phase will have shifted. While I was there I had a look on the table to see if there was any evidence of clipping, I didn't see any although the beam is kind of close to the edge of the 2 inch beamsplitter right after the periscope. I also readjusted the centering on the refl PD, mostly in yaw (the beam wasn't far off). I set up the scope in XY mode with I mon on the X axis and Q mon on the Y axis so we can use that to retune the phase. Strangely, the RF level on the bbPD for the PLL dropped suddenly at around 19:05 UTC. I'm not sure why that happened, the crystal frequency offset sent by beckhoff did not change and the FSS seemed to be locked the whole time. I changed the temperature of the end station laser from 31.35C to 31.45C, the pll is locking fine now.