Primarily this is to accelerate testing the addition (and upcoming removal) of intended recipients in AO mailings. Right now, the faster frequency available is daily, which stretches our testing delays.
Diane: you can change the time at which the AO will run in the Schedule option. Granted, you can do steps of 30 mins between runs, but better than days. What I did in the past to test was request the Participant search to run lets say at 10am, once that run and need another test, then I changed it to run again at 10:30am. Also, make sure you are not restricting the participant.