Experience with Statistics Pre-Req Overrides

Seeing as William and Mary has multiple departments offering various "versions" of an Introduction to Statistics course, how do requests for pre-req overrides generally fare? I took AP Statistics in high school and I'm hoping to get pre-req overrides concerning ECON 307 and MATH 351 in order to take ECON 308 and MATH 352. I have coursework that more or less cover the topics listed in ECON 307 and MATH 351 that I could show to demonstrate my proficiency in Statistics.

I will probably request overrides for those courses next semester, for Fall 2016. Is there an optimal time for me to do this? (Would that time be before registration opens for Fall 2016?)