i assume Boomerang is almost like a channel for retired caroons? teen Titans isn't that previous, yet while they have stopped making new episodes or if the teach has ended then that's probable the explanation why it quite is on there.
ep 42 is Birthmark, the start of Ravens Birthday
ep 46 is The Prophecy, the continuaton of her b-day
Ep 50-52 is The End (1,2,3), the climax of Trigon series.