Change data source of Pivot Tables without changing structure

In short, you cannot avoid changing the pivot table structures. Effectively you have to rebuild them from scratch. I know, we found out the hard way as well. It would have been nice for MS to provide a way to simply change the Data Source types from ODBC to Office365 by simply giving over your credentials, as long as the data source table is 100% the same as what you had before hand.

https://support.microsoft.com/en-us/office/change-the-source-data-for-a-pivottable-afd93524-f7de-432c-84d0-3896fbbc2577