Official Japanese announcement:
https://twitter.com/animalcrossing/status/922448789742542855
https://twitter.com/Nintendo/status/922432707635822592
Basic details:
October 24th at 8PM Pacific / 11PM Eastern, focused on Animal Crossing for mobile, no Switch / 3DS news included, 15 minutes long
Full story over at TBT's sister site Animal Crossing World, cough plug here cough: http://animalcrossingworld.com/2017...-nintendo-direct-coming-tuesday-october-24th/