All credit goes to DIrishB, Lebnyx, Starvel, & SoyaCS.
Original thread here: https://www.thecomicboard.com/threads/marvel-cinematic-universe-timeline.13339/
Timeline reasoning document (credit to @dsethlewis): docs.google.com/spreadsheets/d/18lvrzM9iU62W5bul43WW4cNNGGuJt155SeuHM7ng-R4/...