Per this image, there are six corrals (A through F). I do not know this definitively, but I would put a high degree of confidence on the corrals corresponding to the following chart:
So if you submitted a 10 miler of 1:35, then you can expect to be in Corral B. If you put an estimate of a 2:30-2:45 finish, then you can expect to be in Corral D.
The exact timing is unknown in advance. The timing of each corral release is determined by the % of runners in the field within each corral. Based on past weekends, they use a relatively even rate release system across all corrals. So if you know how many runners are in each corral and the % of runners that makes up of the field, then you can estimate the timed release of each. We don't get that information anymore (we used to). But, we can make an educated guess based on past weekends since many of the weekends have a relatively similar distribution of runners participating. So the following would be estimates. Some times they finish releasing the corrals in 45 min, and sometimes in 60 min. But this is a reasonable guess:
Corral A - 5:00-5:04am
Corral B - 5:04-5:10am
Corral C - 5:10-5:32am
Corral D - 5:32-5:38am
Corral E - 5:38-5:45am
Corral F - 5:45-6:00am
Keep in mind. The 6:00am is kind of a hard fast must be started by. So for instance, last year's race start was delayed until 5:15am. The balloon ladies still started at 6:00am and they just increased the rate of release. Some times the start is on time (5:00am) and they release the balloon ladies at 5:45am. That's why tracking the 16 min/mile pacers is a good strategy if you really want to know on the day of.
@DianaMB333 here is
@Bree 's post with the Galloway pacer information (
link).
The runner tracking isn't available yet. Usually the Monday of race week. If you're on the DIS, someone will be sure to post the link. You just enter "Dennis Holler" and track him and you'll have a reasonable timing estimate on the position of the balloon ladies.