I do not think that Apple is maintaining a full GA level release cycle testing and release planning for a version of IOS that can allow 3rd party apps. The key here is the RELEASE TO GA.

Of course they have internal builds that are signed and allow you to do whatever they want internally, but having a shipping GA with the normal protects and support for all the work and validations that would go into supporting 3rd party installations.

Your resume says you where an Intern at Apple, so I am sure you are correct in the fact that they have an unlocked internal build, however my points are valid about the difference between that and a GA PRODUCTION release.

Note, Apple has some pretty strict NDAs so...