The PO tracking is a bit arse backwards in that it only updates once it has been delivered/attempted.
My three gripes in this case are that 1, no mention of the courier until I started being bombarded with updates from Amazon; 2, that they blatantly didn't bother even pretending to deliver it; and 3, that there's no easy way to speak to someone to establish wtf is going on (either Amazon or the seller).
On point 2, by fudging the tracking, they fulfil their delivery obligations, meaning no recourse for their customer. Generally, sellers don't provide separate tracking numbers for each package, so if only one turns up, the tracking shows a fulfilled delivery obligation, inspite of the fact that half of it is missing. Again no recourse.
Our postie is really good, likewise the reserves although when we first moved here we used to get a delivery every two weeks, with most of the post being dumped in various woods...