I could suggest that you spend some quality time with the Late-Late-Late Show, stay up until 2:01 AM, and click the Check Now button, but this is something you can deal with in the daytime. And you deal with it by opening the Date & Time system preference, unchecking the Set Date & Time Automatically option, entering 2:00 AM in the time field, launching the Software Update system preference, and clicking Check Now. You don’t have to accept any of the updates. Quit System Preferences and relaunch it. Return to the Date & Time system preference, enable the Set Date & Time Automatically option to get the correct time. Software Update will continue to believe it should check for the next update at 2:01 AM. http://www.macworld.com/article/1139860/schedulesoftwareupdate.html