I interviewed 10/2 and got promptly rejected on 10/15. (IS Seattle cohort) Does anyone know if they offer feedback post II R? I can't find anything on their website about this

yes, they do offer feedback but I believe only once. I got feedback my last cycle - never got an interview so the interview feedback section was blank. Don't expect too much concrete feedback and they ask you to first submit a paragraph about your own assessment of your application and, n=1, but my suspicion is that they mostly just affirm your own assessment lol. Basically everything they said for each item was "sufficient experience, but reflect more." "great leadership experience, but reflect more." "illustrate who you are more" etc. Tbf, I WAY over corrected IMO this cycle and got in so idk man