There's no way Trump will simply concede on election night. He's going to question the results under the guise of "people are saying x, I don't know," which is how he spreads all his FUD. I'm going to bet that the election will be called pretty early, ie once the west coast results come in. Hell before it's even called I'd expect his camp to be questioning results, specifically Florida where there will almost certainly be an increase in Hispanic turnout.