The whole deal with USPS Delivery Confirmation # is that they don't actually scan each package as it travels through their various stations on its way to you. That is why they can't call it a tracking number because they don't actually scan each package therefore you can't always track it. That is also why you can occasionally see it travel from place to place, but, often you won't get any updates until the night before delivery, if any.
In my experience it seems to depend on whether your package is one of the lucky ones to get scanned into the system. Unfortunately my current box is not one of the 'chosen ones'.
UPS or FedEx have systems which are more fun to play with as the stuff travels to your house for sure, however, either way I always seem to get my stuff.
I'm envious of that Wetbox too, it is one sexy lil device. Looks like Missy's wetbox from the picture. Only thing is I've not settled on an all day vape yet, so I'd probably have a rough time constantly trying to swap out 3ml bottles.
-Danyulc