released a full-length trailer on Wednesday for the new documentary, which drops Sept. 28.“It’s been 13 years and it’s enough,” Spears’ voice can be heard saying in the teaser.The film is directed by Erin Lee Carr and has been in the works for 18 months, though being released after the FX documentary “Framing Britney Spears.”“This is a two-and-a-half years-long investigative process into the conservatorship,” Carr told the Los Angeles Times.