I was put on hold (pre-interview) at UC Irvine, and after speaking to the admissions director (fantastic thing to do if you can get a hold of that person), I was told to send in an additional letter of rec, if I had any, and also a letter from me as an update and telling them why I want to go to their school. Basically, she said to add things to my file so that they have to review it again rather than having it sit in a pile in the corner. The admissions director told me that they wanted to know how I was doing nationally with this process (ie- was I getting interviews elsewhere?). So the best thing would be to try to speak to someone in admissions (preferably, someone nice and knows what they're talking about) from those schools. I got lucky with this school because the admissions director was so nice. Some other schools- not so much! Anyway, I ended up getting an interview there! So I think being the squeaky wheel helped with this one.