screw it window

The point at which sleeps eludes a person and they decide to stay up all night via some caffeinated means.

Steve, at 11pm: "I have to be up to make a flight in five hours."
Mike: "Anything inside of six hours, I say screw it and put on a pot of coffee."
Steve: "I get 5-7 hours of sleep a night, so my screw it window is 4 hours."