Sonya, from what has been said from RightStart (in webinars, etc)
Edition 2 will have levels A-F, and then the student would continue with the Level G which is not going to be revised.
From their years of feedback, they have noted that many many homeschool families end up taking a year and a half for one or two of the levels, plus I think they added a bit more on a few things. (I think more problem solving, more metric, and some other things.