Hi did you get your delivery?
I have the same issue right now and i want to know if you got the package.
I ordered an iPhone X in late November then change delivery to a UPS store. That went without a hitch - it arrived at the store on the original estimated delivery date.
And then, my wife decided she wanted one too after trying out mine. So I ordered one for her on Dec 21st and got an estimated Dec 26th delivery. It actually arrived at our local UPS center on Dec 23rd. Dec 26th rolls in and the UPS truck shows up in front of our house. After hearing the driver rummage around his truck for about 10 minutes, he looks at me and says he can't find it. I called UPS and they said it might be on another truck and that the drivers are out extended hours until 10PM so I waited. Nothing. Shortly thereafter, the status changed to "Rescheduled" for Dec 27th. Still nothing on the 27th. The driver made a delivery for another package and suggested that I call UPS again. I called again and they said the package has not been unloaded from the container and to wait. I then changed delivery to a UPS store because we would be out and about the rest of the week and the request was noted in the status. Nothing and no status update. Finally, on Dec 29th, I called T-Mobile and, after a three-way telecom with UPS, an investigation was initiated. The T-Mobile rep asked me to stay on the line after UPS hung up. The rep then arranged for a substitute phone that I could pick up at our local T-Mobile store while they're trying to sort out the missing package with UPS. The UPS status has been "Exception - verifying location of package/lost package" since but, at least, my wife is happily using her new iPhone X now.
Long story short, you might call T-Mobile if your status hasn't changed in two days. Kudos to T-Mobile customer service!