I don't know if you're also on Verizon... I tried to check my "documents and receipts" in my Verizon wireless account and there is a Device Payment Plan and a Purchase Receipt document in my account dated Feb 21 (when I preordered), but when I clicked on it, it opened empty documents, nothing showing. So just to check all bases, I just chatted with a Verizon rep to see if the problem is on their end.
He said he does see a pending upgrade on my line, but it has no new device associated with it, as if there's an upgrade order with no new phone. He canceled the pending order on Verizon's end and he said that should trigger Samsung to complete the process through Verizon for my line and have it shipped.
At this point, what could it hurt so I had him to do that and I'll update with anything later if it worked.