!!! I would go ahead and fret about the upgrade clearing

In case it doesn't:
= get an extended life battery/spare for your laptop and watch movies etc
= definitely bring eye shades/ear plugs/noise cancelling if you have it (and can sleep while wearing it!)
= either xanax or ambien is great for sleeping and passing time...try before you fly, not over the counter. In flight is no place to try something and find out there is an issue.
= I also set my watch to destination as soon as we take off
= I also a couple days before start staying up a little later etc
= I also put a priority on sleep period, as in- even if the time is wrong, overall the sleep or lack of good sleep that you may experience is more easily overcome if you listen to your body and get sleep when you can. Sometimes a 15 minute powernap does more for you than fighting it for 5 hours. In the end, you need the sleep and you gotta get it when you can.