Phil Haack invites attendees to join a Git and GitHub talk at the Box Jelly, followed by a social gathering at Kanpai Bar and Grill for drinks courtesy of GitHub. The event is scheduled for Thursday, September 13th, starting at 7:00 PM for the talk, with the subsequent meetup at 8:30 PM. It is identified as the first "drinkup" in Hawaii, offering an opportunity for networking and informal discussions among participants.