Because once the KitKat OTA goes live by VZ (could happen, right?), there would be no way to get on the 12B bootstack (no TOT or KDZ). Right now it seems that most of the devs work with the OTA leak will involve the 12B bootstack. You can always go back to 10b or 11a through the tot method. You might not be able to go back if you take an official VZ KitKat update (could happen right??)
Idk maybe I'm wrong. Just my FUD.
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