Maths and STEM courses in general have never had reading weeks, but for the last few years they've had "breathing week" in week 6 of term, where there are generally no deadlines and (some!) lecturers will temporarily ease off on content pace a bit. They can sometimes be problematic since it can mean later deadlines end up closer together, but it's at least nice to have a chance to catch up a bit without a deadline every few days like the rest of term.
Humanities tend to have proper reading weeks, where they have no lectures and a lot of people go home for the week. Unfortunately we don't get this in maths! (Unless you take humanities courses as unusual options, in which case you might also have those specific module lectures cancelled for that week.)