Gallup Poll On Veteran Voting Today

This is a member only site, though I'm sure the regular media is going to cover it. I must say, I'm a bit surprised at their methodology on this poll. How can results taken in the spring, summer, right after the conventions, be 'averaged' to come to a conclusion 2 weeks before the election?:

To examine the attitudes of veterans more closely, Gallup combined the results of nine surveys* conducted at four different points in time: two surveys taken in the spring (March and May); two surveys conducted in late July and August after the Democratic convention and before the Republicans' convention; two polls following the Republican convention in September; and the three most recent surveys from October. Taken together, these surveys contained 1,512 people who identified themselves as veterans who are registered to vote in this year's election.