Rob to talk to 'Good Morning America' - August 15th

ETA: According to a rep for the Cosmopolis US promo, the interview will be live (source)
ETA2: Accordimg to eOnline and OnTheRedCarpet, GMA reps confirmed that the interview will air live

His "GMA" interview will air live on Wednesday, August 15, from the ABC studios in New York City, a network spokesperson told OnTheRedCarpet.com. The show airs at 7 a.m. ET.

Source