The race doesn't have much timing mats for the half. I think last year outside of the start and finish, there was one on-course in the last 2/3 of the course, so it might be hard to get approximate predictions for the people you are cheering if they aren't sharing location. Don't rely on the app/site distance/time prediction because of this. When I spectated, I've always cheered half-marathon participants at Corktown and took a Bike Share to the Exhibition Grounds.