I had trouble getting into Econ 1B03 last year, mainly because this course is outside of my faculty (faculty of science) and so I didn't have priority. What I did was 1 or 2 weeks into school before the end of the final day to add/drop courses, I went to the department of economics and the lady at the front desk was really nice, she put me into the later time slot class - with Holmes but since I also commute, I just attended the earlier lecture time. There was no issues with this as everything was podcasted and iClicker questions and nothing of that sort were marked. So just try on SOLAR, and if not, go to the department of economics