You can fill out your certification with an estimated number of credits:
12 credits for full-time
9 credits for 3/4 time
7 credits is just above 1/2 time (so you still receive MHA/BAH. Anything 6 credits and below is considered 1/2 time or below half time and you’re not eligible for MHA/BAH.)
The certifying official can put in the estimated number, and when you are fully registered, will certify you for the exact number of credits. Please contact certifying official for further direction.
Current MHA rates can be found here under "Overview of VA Tuition and Fees Contribution"