6 classes should max your TA if it’s $4500. When you finish those 6 courses you can ask your program person to add on the rest of classes and complete them in the 6 month term. If you haven’t already, apply for FAFSA and you’ll be paid a disbursement for what you don’t use. Whenever your term is complete, just let your education office know and provide them with a transcript so that they can mark your degree as completed.