@frob ,
Quote from Microsoft:
In SharePoint Online, items are retained for 93 days from the time you delete them from their original location.
They stay in the site Recycle Bin the entire time, unless someone deletes them from there or empties that Recycle Bin.
In that case, the items go to the site collection Recycle Bin, where they stay for the remainder of the 93 days.
For info about restoring deleted items, see Restore items in the Recycle Bin of a SharePoint site and Restore deleted items from the site collection recycle bin. The Recycle Bin retention time is not configurable in SharePoint Online.
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