So the AP as a means of saving $$$ loophole has been hard closed.
And in hindsight of course that's how it works, both because the university isn't keen on cost savings but also because every student is coming loaded with APs. AP physics isn't "college physics" anymore it's just high school physics and the optional prereq to Physics 101.
Then I took in person classes at 18/19, fixed my GPA and generally did well. The only classes I really struggled with was Japanese and later French.
With Japanese I pissed my Korean girlfriend off, and had to drop it. French I took for a pass/no pass and absolutely failed.
You absolutely can get a BA by 20, but I'd be more interested in WHY you'd want to speed run academia. Sounds really stressful...