But as Phil Lord and Christopher Miller depart the project, their termination by Disney’s Lucasfilm due to creative differences leaves the producers and the DGA with some difficult choices. The key issues: Who will replace them, who will receive directing credit, how will residuals be apportioned and will Lord and Miller even be welcome at the premiere?

At the heart of the matter is the guild’s protection of directors’ rights. The DGA has a strict rule which prohibits replacing the director with someone else from the film’s team except for a brief emergency. It's designed to discourage producers from forcing out a helmer and taking over a picture. And it means that despite speculation that veteran writer-director Lawrence Kasdan, an executive producer on the film who has written the new screenplay with his son Jon Kasdan, could step in to direct, such a move would violate the DGA rule.

But once a new helmer comes aboard — Ron Howard and Joe Johnston are among the names being mentioned — a new question will arise: Who will get the finished film's directing credit?

That’s tough. Presumably, Lucasfilm would prefer that the new director receive credit and will argue that his (or her) vision is the one that predominates in the ultimate film. But Lord and Miller signed on two years ago, and have been shooting since February, with only a few weeks of principal photography left. That gives them a strong claim to credit.

But complicating the matter is the vital role that postproduction plays in a big effects-laden film — and that will all be overseen by the new director.

The DGA doesn’t much like multiple directors to begin with: “There will be only one Director assigned to direct a motion picture at any given time,” says the guild's “one director” rule. But waivers are possible, and increasingly common — especially in the case of established directing teams. Still, it would be a stretch for the DGA to approve three directors' names on a film.

And there's a further twist: While the Writers Guild of America has elaborate rules and even an appeals procedure for credit disputes, the DGA doesn’t.

Instead, the rule is simply this: The DGA decides, and everyone is bound by that decision.

That process, particularly in the case of such a high-profile film, is likely to drag a range of ranking guild officials into the mix. The possibility of according credit to three directors — Lord, Miller and their successor — is likely to seem both logical and unpalatable.

The DGA did not immediately respond to inquiries, and it’s not known whether officials are investigating the situation yet.

And what about residuals? If Lord and Miller should decide to pull their names from the picture, their names would be replaced with a pseudonym — most commonly, “Alan Smithee” — and they might have to forfeit residuals. But assuming they don't pull their names, but are just off the picture, the rules don’t seem to say what happens to residuals in this case.

Possibly, that makes it a matter of negotiation between the departed directors’ agents and lawyers and Lucasfilm — and the new director’s representatives.

Profit participation — backend — is another complication, although not a guild matter. It may already be addressed in the pair’s directing deal, but, in Hollywood, a written agreement is often just a good start for negotiations.

Last, but not least, do Lord and Miller have the right to insist on tickets to the film’s premiere? That won’t happen for a while — as of now, the film’s scheduled release date remains unchanged at May 25, 2018 — but it certainly could be awkward.