Warner Bros. had no comment, but sources said her schedule was already packed and that without a set start date the scheduling became too complicated for the singer.
Knowles was set to play the role Barbra Streisand last limned in the 1976 version as the promising young performer who falls in love with an older fading star, played by Kris Kristofferson in that version.
Jon Peters, Bill Gerber and Basil Iwanyk are producing the remake, with Will Fetters penning the most recent script. Production had to push due to Beyonce's pregnancy and Eastwood took an acting gig on "Trouble With the Curve" during the hiatus.
Studio insiders said that with Knowles now off the project, there has been interest, at least from Eastwood's end, in jazz musician Esperanza Spaulding. Sources emphasized, though, that until the male lead is locked, no discussions or offers will be out to the female lead.
Eastwood has approached a number of top male stars about playing the fading star, including Leonardo DiCaprio, Tom Cruise, Christian Bale, Johnny Depp and, most recently, Bradley Cooper.