I'm not sure if this is a bug or not, but just how big is the Nether now?
Because there are a good few places that makes you teleport to above the Nether if you cross certain points, but I dunno if these are just where the Nether stops you, like on the upper world, but instead of TPing you back a few blocks, it takes you above it instead xD;
Also, I dunno if this is another bug, but I have a sethome to my old Blaze Spawner. I TP there, and it says I've reached the end of the world, but am able to move about. But after a while, I start TPing everywhere in the Nether, to then eventually end up above it. But it's not just when I TP to the old Blaze Spawner, if I walk thought the portal normally, and venture out into the Nether, I then start to TP everywhere again.
It could be just me though, but I wasn't sure if anyone else is having this same problem, or if it's something just happening to me, but I thought I'd point it out.