I think we just have Pentecost, then Rogation Sunday (the green altar decorations come out), and then the Sundays are called 1st sunday after Pentecost right up until Advent. However, I've just remembered that we had the white altar cloths out last Sunday. Hrmmmmm......
OMG, I just pulled out my old "'79 BCP" and you're right! They renamed the season in the '79! In the 1928 BCP they are explicitly the "Nth Sunday after Trinity." The 5th Sunday after Easter is Rogation Sunday.
Last Sunday was green for us, the last until Saturday (green also), the end of Trinitytide. Sunday is purple, Advent, and I think we will agree on that!