Still waiting to hear back from Penn and UCR, but I did get an email from Pitt explaining that they're waiting for more info about funding before they release decisions. Pitt and Riverside are the best fit and my top choices, so I'm really crossing my fingers
FWIW, I reached out to Maryland this morning and they said they're working on negotiating with their chosen candidates, but that I'm on the waitlist. Not sure if that means I'm on an actual waitlist, or if they're just holding off on sending out rejections entirely in case they need to choose other candidates.