I think there are several times that it runs. First it runs after midnight 5 days out, then 4 days, etc, etc. However, I think it does do some sort of in between sweep to "catch" higher level elites that have purchased tickets since their window opened, but before the next window opens. So if a Plat bought a ticket 4 days out or a Gold 2 days out it appears to run for the higher level ie. the plat at 4 days before the Gold window opens, at what exact time, I don't know, but I have been upgraded in the afternoons before on last minute tickets and in the mornings on pre-bought tickets. I really don't know, but it definitly runs more than once per day.