Originally Posted by jswinden
Probably true. I ordered the SO a day after they were announced and got Oct 2nd. I have Prime, and it might be that they are also favoring Prime members though I have no clue whether that is the case.
As to why the SO models first. I speculate it is because all KPW models are setup at the factory as the SO model, that is the software tells it to receive SOs. I said speculate because that is just an assumption. But if they are factory set to SO, then it requires Amazon to flip the software switch off for SO. Perhaps that extra step, if it is as speculated, causes the non-SO delay. Just a big fat guess on my part!
They flip the switch in your account, tied to your serial number. For the existing eink kindles (when ordered as a "gift" so they are not registered), they ship as non-SO, and start displaying ads shortly after you register them.
You can also test that with a FULL "factory reset" (back to new-in-box condition), by erasing the persistent user store (not USB drive) partition, where all your settings are stored.
The shipping of non-SO models first is (probably) just a non-technical policy decision. Perhaps to start generating SO ad revenue early in the shipping schedule?