I'm taking everything with a grain of salt at this point (both conspiracy theories and official narratives) but I heard a report today on the radio that a Pittsburgh outlet is reporting that LE observed a suspicious individual, took his picture and notified officials to be on the look out for this individual 28 minutes before shots were fired. If true, it's beyond incompetence for SS to allow Trump to be at the podium especially after an unidentified person with a rifle was spotted on a roof less than 150 yards from the podium.