UT Austin Appeals

I was recently applied to UT Austin as a Biology major. I was ranked 7/86 in my class and received a 1200 on my SAT. I was also president of Science National Honors Society and volunteered at a local hospital. However, I was told to complete the CAP program. I am interested in appealing. I attended an Early College High School and will graduate with an Associates of Science with a 3.889 college GPA. Therefore, I am going to reapply as a transfer, but I do not know what exactly I should add in my appeal letter. I would really appreciate if anyone could give me some advice.

Higher SAT/ACT.

1200 SAT score is quite low. What is your math score? STEM applicants should target 700+ on math section of SAT.