Phase 1: Telephone interview with line manager.
Phase 2: Face-to-face interview with line manager and a manager from a different team. The first part consisted of a 20 min test about marketing channels and marketing strategies + presentation of said test; the second part is a competency-based interview where the two interviewers asked questions alternatively while the other took notes. God cop, bad cop routine. They were both very professional and nice, though.
However, do not expect ANY briefing from HR - I was invited for a phone interview with HR and then it turned out it was the line manager. And I wasn't told anything about the second interview dynamics or the names of who was going to interview me, despite having chased HR for it. They take at least 48 hours replying to e-mails, or sometimes never do. When I managed to get hold of someone over the phone, they told me to just 'come in on time, sit down and relax,' that 'there are things you can never be prepared for' and 'we don't know the names of the people who will be interviewing you, they will introduce themselves to you on the day.' These are real disadvantages for external candidates.
There was absolutely no communication between HR and the department and, in the end, no feedback - which I found to be really upsetting, considering the amount of effort the application process took.