What are my chances for Regular Admission?

4.0 GPA
1260 SAT
Top 10% of the graduating class
10 AP courses
EC- Marching band (4 years), Beta Club (3 years), NHS (2 years).

Your GPA is good for regular admission, but your sat is on the lower end of the scale for sure. you had the same number of AP classes that I have (i was admitted in feb group) the only thing that could potentially hold you back is the sat score, but are those the only three EC you put on the application

No, I also had FFA, Voulnteer work, and a Veterinarian Program.