Per GSN's schedule page, here's what's listed so far...
December 16
3:00am - What's My Line? (February 2, 1950 - Mystery guest: Phil Rizzuto) (series premiere)
3:30am - I've Got a Secret (October 9, 1961 - "Country Fair special")
December 17
3:00am - What's My Line? (June 20, 1954 - Mystery guest: Doris Day)
3:30am - I've Got a Secret (October 21, 1963 - Special guest: Art Linkletter)
December 18
3:00am - What's My Line? (September 28, 1958 - Mystery guest: Roy Rogers)
3:30am - I've Got a Secret (October 12, 1964 - Special guest: Carol Channing)
December 19
3:00am - What's My Line? (May 20, 1962 - Mystery guests: Sir Edmund Hillary; Diahann Carroll)
3:30am - I've Got a Secret (December 14, 1964 - Special guest: Steve Lawrence)
December 20
3:00am - What's My Line? (June 12, 1966 - Mystery guests: David Merrick; Peter and Henry Fonda)
3:30am - I've Got a Secret (February 1, 1965 - Special guest: Kaye Ballard)