Yes, if they (Clinton camp) expect some major bombshell to be released by Wikileaks and this strategy serves to discredit that, yes. If that is the strategy, then the bombshell must be something HUGE indeed.
Just repeating from above, the early voting likely prevents replacing her. Those votes are already cast, from her most ardent supporters.
The investigation almost certainly can’t close before election day, but again, because of early voting, it doesn’t have to. A lot of undecided may mail theirs in before any final FBI announcement.