J. Kissel, E. Capote, others In short: In order to get more DARM control range, the EY UIM (L1) Coil Driver has been switched to its highest range state State 1, with no analog low passes engaged. This is different from its late-O3, past few years, State 2, which has one z:p = [10:1] Hz low-pass engaged. In only slightly longer: During the rush to get lots of information in the limited time we have with a "low noise" IFO, i.e. the 4 hours when the HAM5 - HAM& gate-valve open, we've been running the DARM loop in a "split actuator" configuration, with DARM_CTRL split to EY UIM EY PUM EX TST Back in O3 (around Nov 2019 LHO:53528), we had assessed the range of ETMY's UIM driver under the "nominal" configuration, where only TIDAL control is sent to ETMY UIM / L1. Under this split DARM actuator configuration, we think that there may be range issues, so we're gunna claw some of that range back. Since we were already on our way "back up" from a lock loss, driving Tidal through EY's UIM, I made the switch by temporarily adding ETMY, L1, 1 to the optics, stage, newState lists in the SLOWNOISE_COILDRIVERS state in ISC_LOCK. T'was loaded, then run, then edits taken out, loaded again, and state saved in the SDF (see attached screenshot).