For me (in Scotland) everyone got the same week ‘off’, so there would be no classes running across the uni. But yeah, the uni made a big point of stressing that it wasn’t a holiday, they called it ‘Independent Learning Week’, because it’s a week for catching up on all your work and preparing for the rest of the semester. I just looked at an old calendar, and I had deadlines due right after ILW (my degree was classics and English), so yeah I always spent the entire week reading for/writing essays. I’d take the weekend preceding ILW completely off, because I did need a break (we had super long terms so everyone was already burnt out by then lol), but the actual week was spent panic working.