AF Academy cadets are in-processed every year on the 4th Thursday in June...which correlates to C, D, E, F .....they are in college so they are here four years...they graduate the 1st Monday in June (4 years later), that's why the Projected Graduation can be June /year

so by selecting June 2016 (when they graduate) from dropdown... C, D, E, and F should auto-pop 28 June 2012 which was the day they in-processed 4 years prior

selecting June 2017 (future graduation date) from dropdown... C, D, E, and F should auto-pop 27 June 2013 which was the day they in-processed 4 years prior on the 4th Thursday in June .....and keep going from there