Yeah, its hard to tell. You will meet there for a short discussion in the morning at 815, and then you have a first round of interviews. These can vary in times from like 930-11:30. Then you have lunch and a tour at 12:15 or so. After that you have a second round of interviews. And these can be scheduled from anywhere between like 230 and 500. So if you get unlucky and have a 5 o clock interview, you will be stuck there till like 6. Thats why they tell you not to book travel till 730. You might be done at 330, you might be done at 600...it all depends. Unfortunately they won't tell you your schedule till the day of since they can change depending on what interviewers are available.