SPO Deleted Items Retention Time, Duration

Question

Hello, regarding deleted items retention time in SPO there are contrary information on then net. Some say default is 30 days in recycle bin and in total (or additionally?) 93 days in second stage recycle bin. Other information says like 93 + 93 days, or even 93 + unlimited until quota exceeds....
What is now the correct answer for default settings? I am talking about regular sites and features not like

And MS itself states here https://support.microsoft.com/en-us/office/manage-the-recycle-bin-of-a-sharepoint-site-8a6c2198-910e-42dc-9a9c-bc5bc4f327da:
By default, items in the Recycle Bin are deleted automatically after 30 days. Regardless of whether or not an item is sent to the users' Recycle Bin or to Site Collection (Second-Stage) Recycle Bin, items are deleted automatically after the number of days that the server administrator specified in Central Administration.

They say by default, how can I modify the default and where in Central Administration can I define the total number of days?

And here MS itself says something different https://learn.microsoft.com/en-us/compliance/assurance/assurance-sharepoint-online-data-deletion:
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.

According to the later it's not like 30 + 93 but 93 + 93. And this isn't configurable either.

Or am I on the wrong track and delete items stay in recycle bin for 93 days in a way or another. If nobody deletes them from the regular recycle bin, after 93 days it is permanently deleted without second stage, If one deletes form recycle bin like after 42 days,it still remain in second stage for 93 days in total? Is this the point?

Answer 1

The first article you're citing only applies to SharePoint Server, not SharePoint Online. The second one has the information you are looking for. You cannot modify the ~93 day window. And, the windows is cumulative, not 30+93, not 93+93, but 93 total. This is the absolute maximum duration for which an item can be preserved (and recovered) from (any stage) recycle bin.

The only way to extend this is to configure a retention policy. If a given item is a subject to retention policy, a copy will be preserved in the Preservation Holds Library for the duration of the policy, which can even be indefinite.