Like everyone else I got the same conflicting notifications (Apple - 9/27 - UPS Text - 9/24 - MyUPS - 9-21). Anyway I called UPS, was transferred to their international shipping (after the recorded message said delivery today 9/21) and she confirmed it is still going through Chinese export customs. Said the delivery date is Monday 9/24. I mentioned that in the past I was told on Apple products UPS had to attempt one delivery before a hold could be authorized. The lady said they had gotten instructions from Apple that for these shipments from China they could accept a hold - which I set up for Monday.
Still much better than 9/28.
Good Luck everyone
BTW - I was at the local Apple Store picking up my iPhone XS and checked out the SS Series 4: It is still noticeably heavier than my Aluminum Series 2 (have to decide whether or not I want the lighter Aluminum Series 4 for workouts - such decisions LOL) and if anyone without a caliper can tell the Series 4 is thinner, well they are full of crap IMHO, because my eyesight is still pretty good and I laid my S2Aluminum next to the S4SS and could not see any difference. (Yes I realize it is less than a mm difference, but I was mentioned several times between the various videos and at the Apple Event.)