Introductory interview with head of the team, then technical data science interview with exercise and finally, interview with product owner. All interviews were well structured but with an informal tone which was very pleasant. I got to ask a lot of questions which they took the time to answer.
Exercise took 2-3 hours to complete - python data manipulation exercise with a very clear and defined task.
Technical interview was about tech stack previously used, how to break down data science problems to a lay person, but also probing what technique would be appropriate to tackle a given problem.