J. Kissel, C. Gray

That lock loss from NOMINAL_LOW_NOISE at 2023-05-24 00:33 UTC was me. 

I was running through the SDF system looking to accept or revert changes to get ready for observing, saw that there were filter differences and tramp differences in the in-loop MICH and SRCL FF in the LSC model, and we thought were Corey was starting the FF test discussed in LHO:69862 a little too early. As soon as I hit "revert" we lost lock. I don't have a screenshot of the DIFFs, but Corey thinks that these filters DIFFs were a result of him accepting the "newer" "5-20-23" filters provided last night just to get us to obseve (see brief mention of the acceptance in LHO:69801, and some discussion of the filters in LHO:69785). We think these showed up as a DIFF tonight because the ISC_LOCK guardian had reset it to the "normal" filters "4-15-23". Or something. 

But clearly switching these filters at the speed of a button click does not make the IFO happy.