Many questionnaires before the actual assessment day/interview day. (Both in the same day). The day is split into both morning and afternoon interviews which you need to select which one you would like to attend. I selected a morning interview as I wanted to be fresh and ready to go. (Also I stayed over the night before as I am from the North). The assessment itself started with a brief and to check you are tall enough. (Please make sure you are tall enough as sadly people do get turned away at this point). Then it was a group task which you are marked on and then a 1:1 interview with another British Airways employee. After this point you wait and sadly some of the group gets asked to leave and the others go through to a 2:1 interview.