I do this same kind of thing when my lawn overseeding is done in the fall. I set up separate fixed schedules for each time during the day that I want it done. While it may seem like a pain to do separate schedules, you only have one zone, and you only need to set it up once. For mine (and this seems like what you would want to do) I have Rain Skip ON, Freeze Skip ON, Wind Skip OFF, Saturation Skip OFF and Seasonal Shift OFF.
