Interesting questions.
Many admissions teams haven’t discussed their policies for next year yet, but will do so late spring/summer. Currently, there are schools who superscore (recalculate a superscored composite), those who consider the highest scores in each of the 4 sections but don’t recalculate a composite, and those who don’t superscore at all. It seems the middle group is the most prevalent when talking ACT.
I don’t know whether ACT’s single section retakes will increase the number of schools superscoring, or increase the number of schools who consider the highest section scores, but it will be interesting to see how this all shakes out.
Another important issue is that the section tests can only be taken on the computer, no pencil and paper option. Many test centers can’t offer computer based testing at all, while some can, but in limited numbers. It’s possible that come September there won’t be enough sites to satisfy the section testing demand. So, register early!
For schools that allow self-reporting of scores and/or don’t require all scores to be reported…they don’t know how many times an applicant has taken a test, so not sure a one and done holds any level of importance at those schools currently, or will in the future.