New worlds reset when in experimental

I have started 3 worlds now with the "new update" box checked under the experimental tab. After a few times of playing on the world and it loading fine, I will go to load the world and it will load with me at spawn with nothing in my inventory except a blank locator map as I usually start with that enabled as well. It is as if the world is loading for the first time, regardless of my previous progress and my inventory is completely gone.