Samsung started rolling out the Android 4.3 update for the Galaxy S4 a while back. The AT&T version in the US also started receiving the update just last week itself. However, AT&T has already pulled the plug on the update.
Although AT&T hasn't yet provided details as to why the update was pulled but it's easy to guess why. Just recently Samsung pulled the Android 4.3 update for the Galaxy S III, citing technical issues that caused several problems on the devices that were updated. AT&T may have noticed similar problems on the devices that received the update.
No information is available as of now as to when the update will start rolling out again.
You are TRULY right.... Specs of the phone are the most Important, because even if the construction are made or plastic or aluminum, You can put a Otter Box anyway
Mine started on 11/14/2013, it went to 2%, I left my phone at home to finish with the new installation, came back 2 hours late the New 4.3 Update never completed. I unlocked my phone, the new version never completed. I checked settings, it was still ...
Should of learned from apple by sending out beta version before public realease tbh..