My DD sounds similar to your kid. She is dyslexic/dysgraphic and is getting As and Bs in her middle school gt program. Our middle school took the opposite approach with our DD. They encouraged us to add every accommodation that we thought DD would possibly need to her 504 and then use the time in middle school to tease out what works best for her. They know the high school and said that if we didn't get stuff in place at the middle school level it would be almost impossible to add anything new in high school.
One caution re the "add everything" approach - We ran into a battling accommodations problem. When it came time for the dreaded PARCC testing to begin, DD wanted to stay in her regular classroom with her regular teacher to help her keep her anxiety under control. The admin people insisted that she had to go to a separate room to get the extra time and sit with some kids with truly challenging behavior. We ultimately dodged the bullet because extra time was built into the testing schedule so DD could stay in the regular class room.
