Thank you for contacting us.
In response to your concern - the scenario where the page is changed or moved won't break the link. The links are generated by Page's unique Id, and not by its name and the link will remain relevant, no matter if you move or rename the page. Only in the scenario where the page is deleted will lead to breaking the link.
Please explain to us further how you are planning to use the anchor links with internal links and what is the scenario that you are in right now - in order to provide you with better solution?
Hope this will help you.
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