A report is a record of what was true when it ran, so we never overwrite one. Submitting the same idea again produces a separate report and counts against your allowance like any other.
Reloading a report you already have costs nothing and never counts. If a phrase in it was still being looked up, a reload is exactly how you pick up the results.
The underlying search results move slowly — usually over weeks, not days — so re-running the same idea the next morning will rarely tell you anything new.