Take this with a grain of salt, but from what I gathered when I picked up mu Note10 +, was that for some reason, the Sim cards that are arriving with devices are marked for delayed activation dates, which is seemingly the root of the issue. If you try to use the SIM that's packaged with the device, it will get black listed because the system has an activation date of at least next Friday or later. That's why most people are getting the late pickup notices. But if you are able to use your current SIM, you have to call your carrier support from your device with tour existing SIM installed and have them update your account with the SIM and your device IMEI.
Not sure who is responsible for this major error, but that's why, even in store, the reps are sitting om hold for a while.
It's also likely partly to be that your device isn't showing as received because of the delayed SIM activation dates or it just may not have been actually received in your stores yet.
I hope this helps clear some things up. I know it doesn't make things arrive any sooner, but try not to take it out on the reps, they're just doing their jobs at this point.