I'll be pulling mainly from this NYPL piece: nypl.org/blog/2019/12/1…
You see the date was intentional, and the purpose was clear.
"Carlos Russell, an activist, professor, and spokesperson for the Black Solidarity Committee, which was comprised of New York City-based educators, activists, community leaders, and politicians."
"On Black Solidarity Day, black ppl were asked to stay home, take the day off from work & school, & not shop. The intent was to draw attention to the plight of African Americans who...
Remember this is always the day *before* election day. Not only do you draw attention but you give people time to prepare to vote and research candidates.