Thank you for your report!
We're tracking this issue in MCPE-150757, so this ticket is being resolved and linked as a duplicate.

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1. play
2. exit like normal
3. enter and find missing chunks

Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response

does it reproduce on any world? If not could you upload affected world? Has affected world been created before C&C update? Could you please provide more details or/and media files. As such we have no repro of this issue.

Also, just a reminder, to make your bug report as effective as possible, please try and include the following steps to reproduce the problem:

Steps to Reproduce:
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Observed Results:
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Expected Results:
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If your ticket does not look like the example given here, then it's likely to be closed as incomplete.

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