I will say the old days (5+ years ago) they use to say attraction A would be down for 3 weeks, in about 2-2.5 weeks in you could expect it to be "soft reopen" Now days, it seems they aren't padding the schedule as much as they use to. If the say it will be reopen on 8/4 expect it to be open on 8/4 and closed on 8/3.
Maybe if you are lucky and there is some pixie dust in the air that day. They will decide to let some guests try it out on 8/3. But honestly, I wouldn't count on it.
I doubt it would reopen that soon. We are there from the 26-31 of July. I wish it was open. They have completely taken down the astro orbiter almost and the TTA needed some work as well. New seats or cushions, paint, and other cosmetics mostly. You can already see some of the painting in photos.