They typically list the pacers in the Galloway booth at the expo, and you can look them up and track them along with yourself. That way you get alerts for both and can compare timestamps to see the buffer. However, at W&D they listed code names for the pacers, instead of actual names so I'm not sure how that will work going forward.
What I did for my iOS tracking spreadsheet was set it up so I just had to input the time I started, and then what time I hit each mile marker, and then have it calculate my overall pace at that point (because I pause my watch at character stops) and then I had another section where I just had to input the time that the balloon ladies or last pacer (whichever I could get) and it automatically calculated what time they'd hit each mile marker based on a 16 minute pace. It was nice to be able to pull out my phone at any given time and be able to say "the balloons should be at about mile X, and I'm at mile Y, so I'm doing just fine"
