Originally Posted by
tryathlete
will I improve my chances (move up on the waitlist rank) if I fareup inside the 24 hour window?
There's no universal rule. The second tiebreaker for upgrade waitlist is fare, after status. If you have 1K status it might be worthwhile if the flight load is tight but not too tight (intentionally vague). If there aren't many seats left or there are many seats left, it could be a waste of money.
edit: actually to respond literally to your question, yes.