I am able to edit the document with OpenXML WordprocessingDocument and remove then add back the header and footer with the updated company information.
I am trying to do the same for OpenXML SpreadsheetDocument,
but I can't figure out how to remove/delete the existing header and footer. I see the DeletePart as part of the OpenXmlPartContainer which
is part of OpenXmlPart : OpenXmlPartContainer. The spreadsheets have header and footers, but I don't see how to access them.