The timing of a pre-election or "October" Suprise is critical. Especially when there are a number of earth-shaking surprises which go off in a well-planned sequence like a fireworks Grand Finale!
Spys and agents provocateurs as well.
Why did Brennan's interview take place at Langley? Was it one of his conditions? Did he demand this for the optics? That the CIA is still loyal to him? Meet on his "turf"?