If a player saves & quits in a danger zone, then when reloading the world the game tries to put the player on a safe block nearby. "Danger zones" include at least the following:

• Nothing but air and void directly under the player (MCPE-140216)
• In lava (MCPE-84546)
• In a nether portal.

The bug is that the algorithm for repositioning the player has not been updated for the experimental caves & cliffs use of negative coordinates. As a result, if a player relogs in a danger zone at negative coordinates they will be teleported somewhere above 0 Y. This can put the player very far from their relog spot (> 100 blocks), and can also lead to death from falling on relog.

Steps to reproduce

1. Load Safe Logout Test.mcworld. This world contains a deep hole from sea level to -44 Y with a smaller 2 x 2 hole to the void in the center. Glass blocks at the top of the big hole can be used to align the player over the small void hole. At -44 Y there is also a small lava pool and a nether portal. The floor at -44 Y extends underground to make a 61 x 4 x 61 room. There are command blocks to switch between survival and creative for convenience. Using the survival mode command block also actives a command block the give fire resistance. The player's respawn point is set to a bed near 0, 70, 0, where there are command blocks to switch the player back to creative mode and teleport them back to the test room.
2. Relog either over the void, in the lava, or in the nether portal. Try each several times in both survival and creative.

Expected results

You are put safely nearby, somewhere on the large available floor at -44 Y.

Actual results

• Sometimes you are put on the surface near the hole at +63 Y or higher. So far away.mp4
• Sometimes you are put in a cave near the hole, anywhere above 0 Y.
• Sometimes you are put in the middle of the hole, just above 0 Y. This is not always evident, however:
  • If you are in creative flying mode, you find yourself in the air at 1 or 2 Y.
  • If you are in creative mode and not flying, you find yourself on the floor at -44 Y, in the central area where it is open to the sky above. That is because you fall to the floor from 1 or 2 Y before the world finishes loading.
  • If you are in survival mode, you find yourself dead on the floor at -44 Y, in the central area where it is open to the sky above. That is because you fall to the floor from 1 or 2 Y before the world finishes loading. Safe zone is a dead zone.mp4 Sometimes you may get to see the fall. Safe zone is a dead zone 2.mp4