I strongly suspect that all of us expecting a MacBook in the UK tomorrow, are part of the same shipment (see previous comment about "UPS World Ease"), so I would be fairly surprised if any of them show as having progressed beyond Cologne at this point.
I also assume that UPS has a plan to get them to us in time - if not their systems would easily be able to project a missed delivery deadline and would say that the packages were Delayed.
Aaaaand my watch just buzzed with a notification from Deliveries... arrival scan in Barking.
I wonder if the UPS tracking data for today was wonky, or if they just trucked them here from Germany during the day. I'm betting the latter.