Hi
Usually you get the .txt file and a PDF for your reference. In the PDF you can check the positions and changes.
Backup only with DB tools - as mentioned.
I would recommend keeping all license files & PDFs from sales.
So in yur case you can keep the old license file (thats already loaded) you received from sales as "backup".
If you do not have your PDF anymore you can use following statement before and after applying the new licence, thats
more or less the view from System Overview/license:
select * from UC_LIC
cheers, Wolfgang