Obama Watch
Letterman's Netflix show will air it's first episode on 1/12/18 with Obama. Best evidence is that the interview was filmed before the 2nd or 3rd guest, Malala Yousafzai, which was taped on 12/19/17. TMZ reported a rumor that Obama's episode was taped a month before 12/19/17.
hollywoodreporter.com/live-feed/david-lettermans-netflix-talk-show-sets-obama-as-first-guest-1071863
tmz.com/2017/12/19/david-letterman-malala-yousafzai-guest-interview-show-netflix/