To rephrase the question....
Could someone please inform me which dates between now and the election it would be acceptable to capture a terrorist without raising suspicion that somehow the entire Afghanistan/Pakistan/Iraq antiterror sweep is somehow being organized in real time by the cold and brilliant mind of George W. Bush?
Well, when you put it that way...which is the problem: You're asking a contrived question to try to lead to the answer you want.
How about this question: In which of the 38 months between September 2001 and November 2004 would it have been a good thing to capture bin Laden? How about that December when he was tied down in Tora Bora? But noooooo, for more than 24 of those 38 months Bush and his government were fixated on Iraq and Saddam, and seem to have forgotten about Al Qaida and bin Laden. It's only now, facing reelection and a barrage of criticism, that Bush seems to have remembered who started all this in the first place.
There is a general answer to your question about timing: The later it happens, the more suspicious it is. If Bush trots out bin Laden in October, it's reasonable to be a little suspicious of a "miraculous save" in the last 1/38th of the game. It could have been any one of 38 months; the month before the election is too remarkably politically convenient to pass off as coincidence.