I was building a 3x3 double ring redstone piston door into my fortress for 5 hours and finally finished it, then deciding to hop off of Minecraft and onto another game when I found myself stuck in a loading screen for "Saving World". I left my PS4 on overnight while in the loading screen and woke up 14 hours later to find that nothing had changed. I then closed Minecraft and returned to see everything reverted to long before I built the fortress, losing me 15+ hours of building and mining and gathering. 
This happens on every world I have and had rendered my Minecraft unplayable.
Please update me with a fix I can do or when the bug is fixed overall.