@CCadmin_Sorin Harvard’s decision day is Ivy day - March, 28. (https://www.thecrimson.com/article/2019/2/22/record-applicants-admissions-2019/)
Princeton - March 28 (https://admission.princeton.edu/how-apply/application-dates-deadlines)
Yale - March 28 (https://admissions.yale.edu/news-and-notes).
I think it’s safe to list all Ivies as March 28.