The ‘divorce’ was applied for January 1964, finalized in March.
The first discussions at Harvard to deny any further extensions to the kenyan commenced in May, 1964.
See summary compiled by matt1234 here
http://www.freerepublic.com/focus/f-chat/2712867/posts?page=1
Barak Sr.’s requests for extensions had been granted in 12 month intervals up until his Aug. 63 application. That one was only approved until April 64 instead of August 64 - a period of eight months. It may have been obvious that he was wearing out his welcome since he didn’t get a 12 month extension. If SAD had any contact with him at all and realized he might not be around past April 64, then it would have been pretty smart for her to get divorced before he was told to go home.