If your child does delay starting college by either method, one option to explore for staying intellectually active and potentially earning credits (without actually enrolling in college and jeopardizing freshman status) is by self-studying and taking CLEP exams.
In case you’re unfamiliar with CLEP: These exams are offered through College Board (like AP’s but with no need to take the course), and individuals can do free prep for the exams and get a test fee waiver through ModernStates.org.
This could be a good fit for your child since she looks like a strong test-taker and is applying to public universities, which tend to have more generous CLEP acceptance policies than some privates. Search on each college’s website for which CLEP tests are accepted, what scores are needed for credit, what requirements they count toward, and how many credits max she could bring in with AP and CLEP combined.
Sounds like a stressful time. Good luck!