Double Cohort refers to the school year 2002-03 at the end of which, due to the graduation of both the grade 12 class, as well as the OAC (grade 13) class, an unprecedented number of high school graduates entered the competitive higher-educations market. This was due to the fact that the old curriculum which provided the OAC option was being replaced by a new system under which the option no longer existed. As a direct impact to OCESS, the senior leadership strata of the club was virtually eliminated, and much organizational experience as well as operational knowledge was lost. The following year(s) of the club's existence tended to be disorganized as a result. This continues to have ramifications on the current club as leaders often find wisdom is documents describing the ways things were done before the double cohort.