purplesmoke - that does seem to be the PhD pattern, for which there is much more posts/data
adelashk - much fewer results posts for Masters here and with the lack of information on the SEAS site, it is hard to tell. But from the past years' history, in 2010 rejections were posted on March 15, 14, in 2009 rejections on March 17 but an acceptance on March 18, in 2008 an acceptance on March 26, in 2007 an acceptance on April 5, and in 2006 an acceptance on April 1. So in total 7 "Masters" posts, all of which were after March 15. It does look like there may be a pattern that may hint to decisions going out earlier in the more recent years. But hard to tell with the limited information.