I have a guess as to who this is :)
Just for other candidate's reference, my advice is the following: Network!
Networking has a 2 birds 1 stone effect. Not only are you maximing your chances of getting an interview (by aiming to get a referral or get put in touch with HR), but during these calls/chats you can get an idea of which offices are hiring and when.
Lots of moving pieces to this as hiring situations change monthly. So, the best way is to just send those LinkedIn messages, pick up the phone, and get talking to people in those offices.
Good luck :)
P.S. For reference,For NYC/Bay Area/Boston specifically I am currently coaching candidates who are interviewing at BCG NYC + Boston and Deloitte NYC