All around nice people and HR was excellent! At every stage they were clear and transparent.
Round 1: phone screening with basic logic questions. Checking that I knew basic probability, dependant and independant, stats concepts. Total time was 15-20 minutes.
Round 2: in-person 1:1. Product analytics case study. If we were to add X feature to Facebook, how would you measure if it was a good idea or not? A discussion ensued with each step leading to the next. Total time was an hour.
Round 3: a series of 1:1 interviews over the course of a day. Some in person, some video conf. Two case studies like above, 1 math (mostly probability and stat concepts), 1 SQL analysis, 1 SQL ETL.
I did not get an offer. HR did call me afterwards and reviewed the feedback from each interview. Super nice folk and I'm ok with their setting a very high bar to enter. Was told that I could check back next year.