Geography shift from world in 18w50 to 19wXX

I haven't been able to play in a few weeks due to my career, however I came back to test on a world that I have put a fair amount of testing into early in this and the Update Aquatic releases. Upon opening the world, I found my location to be similar - as best described - to stepping outside and noticing odd behavior - such as my boat not being placed in water. This seemed to finally occur and I then navigated in a yet similar again direction of terrain to my main location.

Upon its discovery, I find the entire landscape has changed. Large ravine with lava in a nearby Savannah pasture and my border desert residence farm has been uprooted by another level of terrain. Even my basement and all underground dwellings have disappeared. I'm not entirely sure what happened but it's certainly worth examining.