This used to be a huge PITA for me doing inbound cargo as I do on a military base. Not just the relabeling, but also the proclivity of the carriers to place "sortation assist" labels over the MSL (military shipping label) barcodes I need to scan to in-check them. When both of our HHTs failed, without a viable replacement (the ones Big Air Force sent us require reliable Wi-Fi), I took to writing down the last 4 of the tracking number and manually clearing the shipments, and this also obviated the need to scan any part of the MSL as the physical documents were sufficient for the second part of the process.
But more importantly, my new boss (as of three years ago) dug into the regs and discovered that my section isn't supposed to be touching GPC (Government Purchase Card) items at all, and reassigned that duty to the section that actually delivers the packages on base. So the entire relabeling and sortation assist problem became someone else's problem. I feel bad for them, because in addition to the carriers futzing with labels, there's a huge problem with vendors properly addressing the orders in the first place.
