The cable network said in a press release the scheduling move was made "in light of the recent and unexpected deaths of both Carrie Fisher and Debbie Reynolds."
Fisher, 60, died Tuesday after suffering a mid-flight heart attack on Dec. 23. Her mother suffered a stroke and died one day after she did at the age of 84.
"The story of a family's complicated love, this documentary is an intimate portrait of Hollywood royalty in all its eccentricity," a synopsis said. "Carrie Fisher and her mother, Debbie Reynolds, live in the same Beverly Hills compound. The 83-year-old grand dame still has a Las Vegas act, but performing is taking its toll. Carrie's response is both hilarious and heart-rending. Featuring vintage family films that bring iconic old-world Hollywood to life, as well as extensive vérité footage, the film is directed by Alexis Bloom and Fisher Stevens."
The documentary has screened at the 2016 Cannes Film Festival, the Telluride Film Festival and the New York Film Festival, but this will be the first time it is shown on television.
HBO will also re-run the 2010 special Wishful Drinking, a feature-length adaptation of Fisher's hit autobiographical stage production, this Sunday.