Just keep in mind that the difference between a 2:45 POT, and a 2:45-3:00 estimated finish (assuming this is the first drop down choice for non-POT submission) is probably going to be about 2000 people (or less than 10% of the field based on 2018 weekend) and 5 min in starting time (if measuring front of Corral E (5:59am start) vs front of Corral F (6:04am start)). Again assuming rD doesn't change the corral system too much. So I get the desire to have that submittable POT, but know that it will likely have a very small effect on race day if you submit an estimated finish of 2:45-3:00 vs just making it under the cutoff. So keep that in mind when making decisions about reaching for another 10k race or two this Fall for this purpose.
What you choose will be your corral. If you choose 2:45-3:00, then corral F. If you choose 3:00-3:15, then corral G. If you choose 3:15-3:30, then corral H. Again simple.