Hugh unlocked the HAM6 ISI this morning so I could take some quick transfer functions. Similar to what Arnaud found at LLO's HAM6 after the VOPO install (https://alog.ligo-la.caltech.edu/aLOG/index.php?callRep=37394), there are some extra features around the plant resonance. Last I heard, VOPO damping still wasn't functional, so I haven't checked if engaging those affects the ISI tfs, but I think we can say the ISI is probably okay.