Minecraft height limit?

Soon the maximum construction height will be increased. That's why I have a "town planning project". I actually wanted to start with the smaller buildings today, but then asked myself whether the height limit would also be increased in my world that was created BEFORE the update? So if I create a world now and already build something. Or do I have to create the world to have the new limit when the limit has been increased (And NO, I can't play snapshots because of Bedrock Edition and other problems).

I prefer to build when the update is available, a lot will change

Thanks, otherwise it would have been a shame about the building