Hi @Dan Alexander ,
Could you please tell me more about what do you mean by manual "Set Expiration Date"? Is that site-level expiration days for Anyone links set like screenshot below or by the PowerShell command:
Set-SPOSite -Identity <siteurl> -AnonymousLinkExpirationInDays 90 -OverrideTenantAnonymousLinkExpirationPolicy $True ?
If so, site-level expiration days for Anyone links will override org-level setting. All site-level expiration days for Anyone links are the same with org-level by default if you haven't customize them via the methods mentioned above.
Yes. Item-level expiration days for Anyone links will take precedent over the org-level setting. In conclusion, Item-level takes precedence over site-level and site-level takes precedence over org-level.
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