While playing the current hotfix 1.16.40, I found that I can fly in survival mode if the following conditions are met:
1) I am creating a water column
2) on top of the water column I build a platform out of blocks
3) I am below the platform and look up
So I can fly below the platform!
Linked issues
Comments 1

Thank you for your report!
We're actually already tracking this issue at MCPE-48958, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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