A planned attack was coordinated and carried out just hours after the ambassador arrived in Benghazi. Obviously, the thugs knew his travel schedule. And what did they tap into to get his up-to-date itinerary? Her e-mail server. That's hardly "nothing to do with Benghazi"
How do you know that anyone gained information on the ambassador's travel schedule from Clinton's email server? How hard would it have been for them to see him arrive at the airport in Benghazi? How well planned was the attack? Not very. They had about 100 fighters and for some reason did not surround the consulate. They could have captured all of the consulate staff. Why did they set fire to the consulate? That meant that the papers they could have seized were burned.
There is no evidence that they planned the attack for more than minutes before they attacked. There is also no evidence they knew the ambassador was there. Remember that he had been there all day.