Aaah....sorry. Bit of bad news. ):
Seems the details have either changed since I last looked, or I was mistaken...here's what it says in the course calendar's glossary (http://registrar.mcmaster.ca /calen...nt/pg2009.html
is the time between two reviews for a student. Reviews will take place in May and August, provided the student has attempted 18 units of work since the last review or is a potential graduand.
So 27 units would instigate a review, and then you'd have another this year, given that you're taking more than 18 units...but you can pull up by May!