Rumors of Katherine Heigl’s exit from Grey’s Anatomy persists as Us Weekly becomes the latest celebrity snitch mag to report that the Knocked Up star is ready to check out of “Seattle Grace.”

“She’s working really long hours and is ready to move on,” an Us Weekly spy claims.

Earlier this year, reports surfaced that Katherine, ecstatic at her successful reception at the box office with hit flicks like 27 Dresses, was trying to pay her way of her contract with the award-winning ABC medical drama in order to focus on a full-time film career.

And a movie industry snitch believes she may have the right idea.

“She’s a smart one. She saw what can happen with someone like Jennifer Aniston, who was crazy successful on TV, but can’t seem to carry a film, and she tested the waters early.”

Katherine, who won a 2007 Emmy Award (”Outstanding Supporting Actress in a Drama Series) for her role as Dr. Isobel “Izzie” Stevens, has publicly denied rumors that she is looking to leave Grey’s.

Do you think Katherine Heigl will leave Grey’s Anatomy?