[SmartBlondeGPhB]

Here is the full comment on the website:

All students must complete 12 college units prior to going through recruitment/rush. Transfer students and students with AP credits, we would love to see you in the Fall. First-year students, come check us out in the Spring!

Interesting that they count AP credits........

This means formal is in the Spring and the Fall is mainly for upperclassmen and is informal. My alma mater does the same thing and all 4 of the sororities participate in informal.