https://screenrant.com/vecna-stranger-things-villain-whole-time-clues/

Stranger Things season 4 retconned Vecna as the show's villain all along - and key scenes can now be recast as clues to his identity and powers.

We're Never Getting Retribution For Stranger Things' Worst Character, Huh? (https://screenrant.com/stranger-things-angela-bully-eleven-no-retribution-bad/)

Stranger Things season 4's newest Bully, Angela, has unfinished business with Eleven (Millie Bobby Brown), but she likely won't be in season 5.