When Vader first attempts to board the Rebel Blockade Runner at the end of Rogue OneRogue One, we see Vader board first. After he slaughters several Rebel soldiers, we see that his stormtroopersStormtroopers have come behind him. Now this is the exact opposite of what happens at the beginning of A New Hope; the stormtroopersStormtroopers go ahead of Vader and several of them get killed.