I read an article that when the Turk left Stevens (8:30), IIRC, terrorists were already setting up roadblocks.
Haven’t seen that article, but it could be roadblocks were set out of line of site of the facility. most articles indicate there wasn’t much going on visibly except the note of Libyans taking photos. After the ambassador escorted the turk out he gate he went back to his residence. At some point people noted there was what looked like a wedding going on down the street.