I did something similar in my first year - didn't submit coursework, dreadful attendance - and my university never got in-touch till after I didn't show up to exams (and even then it was just the admin department telling me what work I hadn't completed). I've always thought it ironic that Oxford and Cambridge, despite having many of the brightest and most driven students, also have the most stringent supervision: afaik, if you miss an essay submission, of which there are many and which don't count towards your grade, you will be expected to formally justify it. And that multiple missed essays is treated very seriously.