The way the scene is edited, we can extrapolate "extra time" in there. They show Batman at the controls, then they show a long-distant shot,then they show the timer at 0:05. That doesn't necessarily mean he was at the controls at 0:07. Given the speed of the Batplane, it's possible he could've been at the edge of the blast radius.
Or maybe his buddy Superman swooped in and grabbed him, I dunno.
