I'm working on a hypothesis here... A chunk of schools are no longer accepting AMCAS apps (as of the 15th) which means that the applicant pool for these schools is pretty set. Many people who submitted earlier in the season were not granted II's because the schools were waiting to see if there would be better applicants in the pool later on. Now, the pool is decided so they can revisit the people that they passed over in the beginning. This translates to an influx of II's from schools that viewed people's apps a few months ago.
Think this is valid?
Think this is valid?