Does the number of class you take affect the months of benefits remaining?

Let’s assume I use 3.5- 4 months of post 9/11 benefits per semester. I understand that In order to receive full time bah you must be a full time student(12 credit hours or more).

If I decide to take 7 classes in a semester(21 credit hours) will I still only use 3.5-4 months of benefits? Meaning I can finish my degree faster and still have post 9/11 benefits left over?