As per TV Guide, the date has been moved to Sunday, September 30 on OWN (9 – 10PM ET/PT)
Oprah travels to Charleston, South Carolina to meet the hilarious Stephen Colbert. He discusses his private life, his beloved TV alter ego and his friendship with Jon Stewart. He also opens up about losing his father and two brothers in a tragic plane crash.
Source: TV by the Numbers.
(Thanks to Mrc for the Tip and dentry for the update!)