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This issue was raised by an SDP community member via the serviceticket on 1 June, 2022.
Summary of issue
This occurs when publication child pages are scheduled to publish at the same time as the child pages.
Suggested workaround
If you are setting a publication to publish at a specific time, publish the publication landing page 1 minute before the child pages. You will also need to republish the publication landing page after the child pages have published so that they appear in the index on the front page.
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