unamochilla2 said:

Or the script being compromised due to Harrison's injury and his time out. His rumored co-lead role may be downgraded to supporting.

This could possibly cause certain changes to the script.

In ESB, with Hamill's injury to the face from a car accident, they implemented that injury into the movie by having the Wampa swipe at his face. That actually worked out very well and added realism.

I'd be curious how they might implement Ford's injury into the story (IF they go that route).

Or... if Disney is has obtained a complete technical readout of Harrison's broken leg (and are concerned about the quality of the film) it is possible, however unlikely, that they will find another release date, and push it back.