At least by September 1st, please!
Ceremony starts at 4:30 pm. There will be parking attendants to show you where to park. But ubering is recommended for the drinkers out there.
Semi-formal. Don't over-think it. Just look nice. Don't wear a white dress like Kelley. Don't look sharper than Austin (impossible to do anyways). Ceremony and reception will be held (mostly) outside.