When I did the 4 year course as it was before the introduction of fees, we were usually in 3 days a week on average, sometimes more, sometimes less. The peak has risen for 4.5 full days you’re expected to be in. Those don’t necessarily translate to 4.5 full days of teaching, which can be a pain. Being dragged in for a lecture that’s all of an hour long and starts at 3pm is something timetabling can consider to be entirely reasonable.
Something to consider is that timetabling is not always fixed. Things can move about on a weekly basis. It was rare that I had any two weeks that were identical. But you do get the timetable in advance at the start of each semester, so you can plan in advance. It’s just a pain.