Mail order, trust

In the US, I made numerous purchases through the internet; delivered to home.  The biggest headache, which has been much parodied on YouTube, is that you're never home for a package that requires a signature.  They've made attempts to remedy that problem by adding drop-boxes or convenient pick-up locations.  There are extra layers of trust required over just buying something at brick-and-mortar. 

Now in Australia, I've made a few purchases; not as many.  And already, I've run into the nightmare - the missing package.  For a couple of weeks, the internet tracking said it was enroute.  Considering I made two purchases from the same retailer on the same day, both were in stock and one was delivered, the several week delay started seeming suspicious.  So I called the Australian Postal Service. At 4:30 pm, and after 17 minutes I started getting concerned that I was going to be on hold until after 5 pm and everyone had gone home.  Fortunately, it was holiday overload keeping them busy, aaaaand...  most peculiarly... although the web site was showing that the package was still enroute, a courier somewhere in the system (but not visible through the web interface), had recorded that they dropped off the package and got a signature.  So why wasn't that recorded in the web interface?  And so now they are investigating.  Australian Post has a pretty good reputation, but when the courier dropped off the other package, they were running away as I opened the door, and when I said something about signature required, they waved me off.  Did the other package go to the wrong address?  If it's lost forever will I be able to purchase another item at the sale price?  I am supposed to get more information within five business days.