6 January 1955: birth of Rowan Atkinson, who played the Ninth Doctor in The Curse of Fatal Death.
6 January 2009: death of John Scott Martin, Dalek operator and player of many parts in Old Who.
ii) broadcast anniversaries
6 January 1968: broadcast of third episode of The Enemy of the World. The one surviving episode of the story, with Denes kept prisoner in a corridor (!), Victoria working in the kitchen, and Salamander realising that something is up.
6 January 1973: broadcast of second episode of The Three Doctors. The Second Doctor, the Brigadier, Benton and the Tardis are transported to Omega’s world to join the Third Doctor and Jo.
6 January 1979: broadcast of third episode of The Power of Kroll. The Swampies try to execute Romana, the Doctor and Rohm-Dutt, but they manage to escape by screaming; and Kroll rises from the deep.
6 January 1982: broadcast of second episode of Warriors of the Deep. The Silurians attack the seabase and the Doctor and Tegan are trapped by the Myrka.
I’m genuinely astonished that you got a reply from 5 of the 6 (and having read the update, all 6)… Last time I quizzed a candidate for local office on the doorstep about the frankly awful and ever-diminishing local bus service, he had absolutely no idea which routes ran, how frequently or what the numbers were. (As there are only 2 bus services, frankly, extremely poor). I didn’t vote for him. I wasn’t going to vote for him anyway, but I felt berating him on the doorstep might take up time he could be using to recruit others…
Sad to say, he got in, and has since been re-elected twice…