3rd grade fl fast

My son is in 3rd grade at public school in florida. He has a solid iep and is in a self contained class for majority of the day. He has asd and severe language delay. He wasn't speaking until he was 6 and now at 10 is still a struggle. He reads at a beginning 1st Grade level. He did repeat prek due to covid year. If he fails the fast test today will they retain him or can he be good caused?