Got asked to come to an assessment day at the V&A. Arrive early morning and it took about 2-3 hours, consisting of an introduction, two group activities, a break, a chance to talk with some staff, and then a 1-1 interview that lasted approximately 10 minutes.
I went in with a lot of energy and it paid off, I was able to have some great conversations with other candidates and staff. The staff were really lovely, bubbly, and encouraging, and the other candidates (~15 of us) were supportive and friendly.
At the end, we were asked to fill out some security details and get our forms checked, then we were sent on our way.
Overall a very pleasant day, especially if you make the group activities fun. I really enjoyed myself!