There are a few possibilities as to why it was pulled. Could be to strip out anything related to LTE connectivity that might have been left over in the stock image. This would be prompted by the recentÂ developerÂ activity that got LTE working on AT&T in some locations. It could have also been because of aÂ criticalÂ bug issue inside the factory image that caused issues.
We will keep an eye out int he usual location to see if anÂ explanationÂ is issued by anyone. Until then, if you have theÂ originalÂ factory image, be sure to keep it some place safe.