New EW article. Basics:
Reshoots were planned in advance, this is common practice with blockbusters.
4-5 weeks of reshoots- due to the logistics of the actors being available at the same time- some are working on other films.
Mostly character development and personal scenes that fit in with what was shot.
Rogue One is different than TFA, a war film, and that is intentional.
Outside of Lucasfilm only Bob Igar and Alan Horn have seen a cut.
I’m guessing that if anything violent would be cut, it would be because of a potential R.