Interesting....Where are you guys seeing this on the UPS site? Mine is in Louisville as of 12:07am central time and it probably ain't budging down here to Nashville until tomorrow sometime.
I think that note was faked. I couldn't find it on the UPS website.
Depending on capacity and logistics of each hub, it may be impossible to "hold" early arrival of shipments, and they will be treated like a normal shipment.
Source: UPS