So who believes there was an AQAP threat to the US embassies in Northern Africa and the Middle East?

Supposedly, the SIGINT system made famous by Edward Snowden is credited with capturing chatter between AQAP leadership. Particularly of interest, according to anonymous government sources, was a notification between Ayman al-Zawahiri and his subordinate leadership that everything was ready for an imminent attack. This prompted the US government to shut down nineteen embassies and "issue a general travel advisory":http://worldnews.nbcnews.com/_news/2013/08/01/19820594-us-issues-worldwide-travel-alert-over-al-qaeda-threat?lite through the month of August. Meanwhile, despite the imminence of the attacks, nothing has happened except for some