Actually, all Apple does is print out a form with your name, tracking number and lines for your signature.
If you type up a letter to UPS, with your Tracking Number and Name/Address on it, you can just sign it yourself and stick it on your door.
All the UPS driver needs is your Signature on a piece of paper saying you got so-and-so package.
There is no notification sent to anyone using the online site to print out a Pre-Sign form, nor are there any special code numbers on the form.
----------
Also - if you miss the first delivery attempt, they'll put a note on your door and you can just sign that note and leave it on the door. Monday, when they do the second delivery attempt, they'll drop it off as long as you checked off the box on the UPS sticker to leave it there.
But, then you'll have to either wait till Monday or go to the UPS hub yourself and pick it up.
They don't do weekend re-delivery attempts unfortunately.