I took Kin 1Y03 in first year and 1YY3 in second year, and the problem really was registering for Kin 1Y03 in first year. But Kin 1YY3 was almost always available and there were several empty seats in the lecture hall as well. But anyway, being a second year, you'll get to pick your courses before 1st year Life Scis, so that's definitely a plus. However, be sure to get onto SOLAR asap just in case. Oh and if you don't get in on your first try, no worries. I know a lot of people who were able to get into the course throughout the summer and even in the first week or so of school. There are 120 seats saved for upper year Life Sci students (according to Dr. MacDonald). Also, every year is different based on demand, so no one can really expect what it will be like. However, the course is in high demand, but definitely not impossible. My advice is to get onto SOLAR asap or keep trying and don't give up!
Also, there's no one you can really email because they'll tell you to keep checking SOLAR, they won't really do anything more. Let me know if you have any more questions!