I had two sets of phone interviews. Each set of interviews had 2, 45-minute calls with mid-level managers. The questions consisted of mostly case questions, with some behavioral questions (mostly about times I have used data to solve a problem). After my first interview, it took them about 6 weeks to get back to me to schedule the next round of interviews. I followed up with my recruiter every two weeks to see if I had an update on my status. My advice on case question prep… worry more about understanding what frameworks you use to answer specific types of questions, as opposed to planning out for specific questions. Other people may have had a different experience, but I did not get any questions I planned for. I think they purposefully retire questions quickly, so people can’t prepare for them specifically.