Hi Paul,
Here is a listing of the launch windows for STS-117 from Bill Harwoods' Space Page site:
For April and May in GMT time and Eastern Daylight time (for KSC in Florida)
DATE/GMT...TIME/GMT.......TIME/EDT
04/21/07...19:23:51.068...03:23:51 PM
04/22/07...18:58:06.322...02:58:06 PM
04/23/07...18:32:24.020...02:32:24 PM
04/24/07...18:09:52.881...02:09:53 PM
04/25/07...17:44:10.000...01:44:10 PM
04/26/07...17:21:39.351...01:21:39 PM
04/27/07...16:55:56.138...12:55:56 PM
04/28/07...16:33:25.992...12:33:26 PM
04/29/07...16:07:42.409...12:07:42 PM
04/30/07...15:45:12.819...11:45:13 AM
05/01/07...15:19:28.665...11:19:29 AM
05/02/07...14:56:59.956...10:57:00 AM
05/03/07...14:31:14.982...10:31:15 AM
05/04/07...14:05:32.387...10:05:32 AM
05/05/07...13:43:01.570...09:43:02 AM
05/06/07...13:17:18.427...09:17:18 AM
05/07/07...12:54:48.271...08:54:48 AM
05/08/07...12:29:04.690...08:29:05 AM
05/09/07...12:06:35.486...08:06:35 AM
05/10/07...11:40:51.407...07:40:51 AM
05/11/07...11:18:22.586...07:18:23 AM
05/12/07...10:52:37.841...06:52:38 AM
05/13/07...10:26:55.171...06:26:55 AM
05/14/07...10:04:24.631...06:04:25 AM
05/15/07...09:38:41.300...05:38:41 AM
05/16/07...09:16:11.446...05:16:11 AM
05/17/07...08:50:27.700...04:50:28 AM
05/18/07...08:27:58.776...04:27:59 AM
05/19/07...08:02:14.637...04:02:15 AM
05/20/07...07:39:46.485...03:39:46 AM
05/21/07...07:14:01.406...03:14:01 AM
Source:
http://www.cbsnews.com/network/news/space/currentglance.html#WINDOWSFor a window in June, opening around June 8th, the launch time would be around 7:30 PM EDT or 11:30 PM GMT with the launch time moving earlier 23 minutes per day. Hope this helps you out. Thanks.
Richard