The process is fairly lengthy and requires a great deal of effort. First there's a very quick initial phone call to confirm and get a few more details on your CV (education, expected graduation, why this particular service, what does strategy mean for you) and if there's a match, then you'll be invited to the Business Case Day. It's easier to do it online, no preparation is necessary but you need to show that you work well in a team and your soft skills (let others speak, listen to them, take the floor etc etc). If the feedback is positive, you move on to the HR round, a very classic question and a technical round (depending on the department, technical or behavioural questions "tell about a time when you faced challenges". If both rounds are positive, then you have the final interview, a basic but very important motivational question. HR can take very long time to give feedback but the quicker they give feedback, the highest chance you move to the next stage. Got my offer 24g after the final interview.
Whole process took 5 weeks.