My package was found and delivered today. It was supposedly misplaced at the post office. Odd, since according to the tracking website it was delivered at 5:24PM yesterday. Either way, I'm just glad it arrived. Ironically the other package that was also listed as delivered over a week ago mysteriously arrived today too. USPS appears to have some serious issues these days. Perhaps it's because they're going broke?!
I worked for the USPS call center a few years ago. I think I can explain the scan codes you saw.
The first package was probably supposed to be scanned, "arrived at delivery office". Somebody had the scan gun set for the wrong "delivered" code. So everything showed delivered instead of as arriving at the office. It's not that hard to do, the codes are numerical. If you fat finger one you can get some really odd things showing up on the website tracking info.
The second one isn't that big of a mystery either. The person who got your box was honest. Whomever got your box put it back out for the mailman. Most delivery mix ups happen on the same route, so your mailman probably just dropped it off at the correct address with the rest of his stuff.
...Yeah, your post office does seem to be slightly incompetent. Most of them are much better.

Well Dan, not exactly true(at least from my point of view) You are currently changing up ALL of your comfort areas to give up what you have for what may be. Pretty sure that takes a little testicular fortitude
I have to find a way to use testicular fortitude in a sentence now... hmm.
Right, no one ever complains about the post office.
Sure they do, but very few people actually file complaints.
I'd say they are about 3/8".. It appears as though an extremely small head and torso pop out of one end and basically drag the "cocoon" around.
I agree that it's local to my part of town. At least as far as I know. The people at my local post office are literally some of the most rude, unfriendly people I have met. Rivaled only to the folks at my local DPS. I worry that if I complain that my horrible service will get even worse!
It might interest you to know that if you file a complaint through the usps 800 number they all go to the actual postmaster for the delivery office. The postmaster generals office also sometimes monitors those reports, so the offices can't blow them off.
They aren't slimy and gross like a maggot, though. For that matter they aren't larvae-like at all. They literally look and feel like a dried up little leaf. Very similar to the little leaves that fall from either mimosa or bird of paradise.
Hmm, maybe something's larvae wraps leaves around it's self and uses it as camouflage? They remind me a bit of caddisfly, but those larvae like to live in the water. They will make a kind of shell around their back ends with whatever is at hand.