(L-R) Chris Miller and Phil Lord. Getty On Thursday, Lucasfilm announced that Oscar-winner Ron Howard would be taking over the directing reins of the untitled Han Solo movie following Tuesday's shocking news that its original directors, Phil Lord and Chris Miller ("The Lego Movie," "21 Jump Street"), were fired.

Lucasfilm president Kathleen Kennedy, who is also a producer on the movie, would only go so far as to say in a statement that both sides had "creative differences," a term often used in Hollywood when a falling out occurs.

But what were those differences?

Entertainment Weekly is reporting that the main friction between the directing duo and the Lucasfilm brass was the level of comedy in the movie.

Han Solo, the legendary space smuggler from the "Star Wars" saga, was always played with a sarcastic humor by its original actor, Harrison Ford. So the idea that a movie focused on a younger version of the character, to be played by Alden Ehrenreich, would have some laughs.

But according to what sources tell EW, the duo thought they were making a full-on comedy.

"They thought they were brought on to make a Phil and Chris movie," said a source. Or as EW writer Anthony Breznican put it: "Lucasfilm and producer Kennedy believed Lord and Miller were hired to add a comedic touch; Lord and Miller believed they were hired to make a comedy."

Lord and Miller allowed their actors, which includes comic Donald Glover playing Solo's friend Lando Calrissian, to improvise, sources told EW. In some cases the directing duo significantly changed parts of the story while shooting on set.

Lucasfilm president Kathleen Kennedy. Gustavo Caballero/Getty In the world of "Star Wars," this is a major no-no, going all the way back to when George Lucas oversaw the franchise. So when Kennedy and her team saw dailies and found actors improvising and scenes being shot not as they were planned on the page, the relationship began to sour.

EW learned that when reshoots were planned, Lord and Miller began to push back, believing they had found the right movie, and it deviated greatly from what screenwriter Lawrence Kasdan ("The Empire Strikes Back," "The Force Awakens") had penned.

Lord and Miller were told they were fired on Monday.

This is an example of two sides that were not right from the start. It would be hard to imagine Kennedy and her team didn't realize how Lord and Miller work. Perhaps the thinking at Lucasfilm was that the duo were flexible to toe the line and play by the "Star Wars" rules. Clearly that wasn't the case.

The firing of Lord and Miller came as a shock to many because, up until this week, there weren't any signs that there were troubles with the movie. As many are looking back for hints, i09 caught something Lord said at last year's Star Wars Celebration when talking about the character of Han Solo:

"I sort of relate to him. He doesn’t want to do anything that he’s told. When told not to do something, it makes him want to do it more."

That has a whole new meaning today.