Based on the information on that site I would guess that the flights from Shenzhen to Anchorage directly are probably packed with apple products (given that they are on UPS planes) and that the ones that stop in South Korea have much less cargo that we care about (since they seem to be passenger planes with limited cargo hold).
That clears up a lot for me. I wasn't clear on why Flight Aware consistently had one flight from Shenzhen and then 5 flights from Anchorage, it didn't add up. I didn't think the Shenzhen flight was 5 times as big as the anchorage flights. The commuter planes to carry cargo would explain those additional flights.
Where does flight aware get its information? Do they track ALL flights originating from Shenzhen that are UPS related, or do they know specifically the flights that contain apple product, or even better apple watches?
I bet this is answered somewhere in this thread, but I've read most of it and didn't see the answer.