That's a good question! The library is open all night on the evenings before exams. The first exam during April finals is on Monday, so we begin the 24 hours/day on Sunday.
We have always offered longer hours on the study day, even before the library began staying open 24 hours/day during finals week. During April finals, we are open until 10 p.m. on the Friday and Saturday preceding finals week. We normally close on Fridays at 8 p.m. and on Saturdays at 6 p.m.