Before accepting the offer I'd advise you to ask employers whether the value of spending a year immersed in the English language, but also only 72 ECTS worth of instruction, is worth more to them than having the 120 ECTS which is standard in mainland Europe.
As for how exams and assessment works, in general you will have two semesters per year of about 15 weeks, at the end of those semesters you will have exams, somewhere just before the middle you may have midterms. You might also get assignments during lecture periods. To make it more complicated, your holidays are split by terms rather than semesters, so you may do 12/10/8 instead of 15/15. As a masters student I think you will also have your thesis/dissertation which you do in the summer.