I don't think that is how it works... Last year I got a rejection letter around 10:45 pm on March 29th. But I'm not sure if that means that no wait list or acceptance letters were sent after that time.
@AliGee, I've applied to Western too! Do you know if they use grad school courses in the GPA calculation? I have a 3.7 and already got a rejection from McMaster. Still waiting on U of A and U of T and starting to really hate this waiting game!