I checked out the Chimney Swift Roosts for the first time last.  I started at the original roost, as the birds seemed to be focusing on it, making some of their usual test flights toward it.  By 8:25 it was obvious that while there was interest the birds were not going to be using that chimney.  At that point I went and checked the chimney they have usually used at the end of the season.  Sure enough from 8:30 to 8:45 I counted 75 Chimney Swifts enter.