Pre-shipment is when label is printed. So, as already mentioned, it might never made it to post office. I know some people who do drop shipping and they use that trick to placate customers while waiting for China inventory to arrive. But there are delays for distribution center scans too. I ship from Brooklyn. Last week it was two days for initial acceptance if you drop to a collection bin. But about 10 percent didn't scan at all and just showed up on route 4-5 days later. So, I had to start waiting in line and begging to scan all my packages. Luckily, my local postal guys are awesome :) If your sender went through retail window and asked for acceptance scan then there should be separate 'package arrived at a carrier facility' log.