I applied to RPC for the MA/PhD. I submitted a cluster statement as well, if that adds anything. Also, for what it's worth, i saw on the 2018 comm forum on gradcafe that some were accepted/denied on March 21/22. I don't know how to feel about my chances without an interview, but @transrelativity 's experience (not interviewing at a school but getting accepted) gives me hope!
I did not interview at Northwestern, but I still have yet to hear anything. I emailed the department a couple weeks ago to (politely) ask when decisions went out, and the department said "we have until mid-March." So, in short, still waiting!