Pretty easy. Don't watch preseason games because they are boring and not broadcast out of market.
Google highlights and film breakdowns of the results after the game.
Trubisky threw what like a couple of dozen passes all preseason? Pretty easy to go find those on the internets. Didn't bother to search them all out. Saw like say 7/10 or something like that. Did I miss the throws where he lit the world on fire?