ii) broadcast anniversaries
9 January 1965: broadcast of "Desperate Measures", second episode of the story we now call The Rescue. Koquillion is unmasked as Bennett; the Didonians kill him, and Vicki leaves with the Tardis.
9 January 1971: broadcast of second episode of Terror of the Autons. McDermott is killed by the chair; the older Farrel by the doll; and the Doctor and the Brigadier are abducted by Auton policemen.
iii) date specified in canon
9 January 2000: Jack Harkness becomes leader of Torchwood Three, as explained in Fragments (2008).