both survival and creative will cause you to not get launched back in the air
if you hit the edge of the slime block! and even take fall damage in adventure/survival mode.

how to duplicate the glitch:
1: set down slime block
2: stand atop the slime block
3: hold shift and move to a side of the block (or a corner)
4: now fly up some blocks (40-50 blocks)
5: do /gamemode 0/2
6: and you will die...