The book to film adaptation of Looking For Alaska won’t begin filming until early next year in light of recent casting disagreements between members of the production team.

The Wrap reports that plans to film Looking For Alaska this fall in Michigan have been scrapped because the team behind the film has yet to decide who will star as Alaska Young, the film’s titular character.

“The movie hinges on whether the audiences connects with the Alaska character and the filmmakers wanted to make sure they took the film to find the right actress rather than rush a decision to make a fall start date,” The Wrap says. “Paramount, director Rebecca Thomas and producer Wyck Godfrey will go back to the drawing board after being unable to agree on a choice.”

The two frontrunners for the role of Alaska were reportedly Anya Taylor-Joy and Autry Haydon-Wilson, but Paramount may reboot the search now that they have more time. The Wrap thinks they may try to go for a “more established actress” now that they have a few extra months to decide.

The delay in production means that the actors who they selected to play Miles and Colonel — reportedly Charlie Rowe and Logan Miller — may not be available for the January 2016 shoot. In other words, it’s possible the two lead male roles may be recast.

The Looking For Alaska book, published in 2005, was John Green’s first YA novel. It is considered by many to be one of his best.

Paramount decided to greenlight Looking For Alaska after the success of The Fault in Our Stars film last year. Earlier this summer Fox released their second John Green book-to-film adaptation Paper Towns, but it didn’t do as well as Fault (They respectively made $31 million and $124 million domestically).

It’s too early to know what this means for Looking For Alaska’s release date, but presumably Wyck Godfrey and Paramount are still hoping to get the film in theaters sometime in 2016.

If so, it won’t be the only John Green book coming to movie theaters next year. An adaptation of Let It Snow, co-written by Green, will open December 2016.