The IMSA recently announced that three of their events would be rescheduled due to the coronavirus. This includes the Atlanta area Petit Le Mans which has been moved back 1 week to October 14-17. It was originally scheduled for October 7-10.
With the impacts of coronavirus still up in the air we will have to wait and see if there is any additional impact.
Tickets are currently on sale: https://tickets.roadatlanta.com/online/index.php3?shopid=104&language=9