I have a kid who is scheduled to graduate next spring at age 20, after 3 yrs at a state flagship. Started college with 52 credits, & has been able to take a light course load every semester. Some things I learned along the way:
It really really pays to look at the colleges’ policies regarding AP credit. Huge variances in what scores you need to get credit & how many credits you get for a particular score. There are also idiosyncratic rules like some colleges won’t allow AP credits to fulfill “core” requirements. Another issue is that you have to decide on your college choice before you know the senior-year AP test results.
Do a lot of research on what college classes taken while in high school will be accepted. Some (usually elite) colleges won’t accept community college classes or online classes. A lot won’t accept college classes that were conducted off campus or with only high school students.
Some colleges have limits to the amount of AP and/or dual enrollment credits they will accept.
The main issue socially that my kid has encountered is that friends tend to be a year older, & the friends enjoy hanging around bars that my kid can’t get into (town is brutally rough on fake IDs).