NZ Post - Scanned Delivered, not delivered

Is anyone else noticing an increase in NZ Post parcels being scanned as delivered well before they actually are? I've had about four (that I know of) this year. One said delivered early in the morning but wasn't delivered until late in the evening. Another was delivered the day after the claimed delivery. One was scanned delivered twice with another update in between and only the second delivery was the actual delivery. I know at least instance was a misdelivery - I lodged a claim with NZ post who said they'd misdelivered, recovered the parcel and were now delivering but another week passed at which point they said they'd lost the parcel again and would have to refund.

I just had a frustrated customer get in touch as their courier parcel had only just arrived after a week and a half. The tracking had shown it as delivered on the 5th of July so I had thought everything was fine. She clearly hadn't looked at the tracking details herself (though I had e-mailed them to her when I let her know the parcel was sent) and it seems the parcel just arrived today (Sunday). 

There may be more. These are just instances where I'd been in touch with the customer regarding late delivery, or received complaints. 

I realize some may be misdelivery but I wonder if some couriers are cutting corners and scanning everything as delivered when they pick it up from the depot or something strange?