I recently emailed back a forth with the admissions office at UofM, and I thought the correspondence might be useful for those of us retesting in December.
Tldr; Apply as soon as you can, if you improve your score they will reevaluate you ...
How are you handling the FAFSA and application timing?
My situation is a little unique; I have to write waivers for parental information for schools that require it of older students (it's a long story, we're not in touch, but I was never ...