IF we do that, Nightwing may call Alfred to get the Bat Jet, Nightwing cant get to Gotham by motorcycle in less than a day, unless the Flash grabs him, which Batman is saying not to go, so i guess its up to the Flash at this point. "Bruce Wayne" still needs to make his trip home, so he likely wouldn't show up in Gotham till late the following night, unless he stays in metropolis longer.