>>59028424I tried looking up why March 7 (because I'm not on Xitter and don't care to investigate that post of yours), and the best result I could independently deduce was that it was the dub air date for XY053, where Serena raced her mom and was able to fully commit to being a Performer. To my knowledge, the only "Serena days" are February 2, Y's birthday, and October 27, SatoSere Day.
