As we know,some of the rest part of 'Caves&Cliffs' Update has been put in Experiments.The height limit of the world should be widen with Experiment:'Caves&Cliffs'.
In fact,it is only true for World Type:Infinite,but it's ineffective to 'Flat'.
Days ago,before I wanted to start to build ****************,I tried to put blocks under zero,but a message came and meant that the lower limit is y=0（The world type：Flat）
So,Is it contradictory between the fact and the tidings of the Update Plans,isn't it?
To sum up , it is possibly a bug to 'Flat' that's what the update probably forgot or left out.
Thank you for your report!
We're tracking this issue in MCPE-121849, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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