The old text was confusing, but the new one doesn’t say anything about no rewards, so I think it’s clearer that a re-roll is just what it sounds like: you get a new task to complete and when completing (or skipping) that one, you get the expected stars.
Wonder how much a reroll will cost. And how it will work. Imagine replacing a “complete 3 dungeons” with “complete 6 dungeons” 