Quitting in a 2 block tall space will move the player west when the world is reloaded
Samsung Galaxy S6 Android 5.1.1 MCPE 0.15.0 Beta build 1 tested in single player survival and creative
To reproduce, place a block directly above the player and quit and reload the game. Observe the location of the player has changed on loading. The player is slightly west (and a bit up). This only happens if there is a block directly above the player.
If there are solid blocks west of the player, the player will spawn partially inside those blocks and start suffocating.