None that caught my eye.
ii) broadcast anniversary
24th August 1968: Broadcast of episode 3 of The Dominators (1968). Zoe, Cully and the other Dulcians are being used by the Dominators as slave labour. Cully escapes, but the Doctor is captured, and yet another episode ends with falling masonry.
iii) date specified in canon
24th August 2006: Maria Jackson and her father move in across the road from Sarah Jane Smith; later that night Maria sees Sarah talking to an alien being. (SJA: Invasion of the Bane, 2007)