Help with updating and archiving data
You have two things.  You need two tables to handle such.


A record of Invoices.  Once an invoice is issued, the row(s) that describe must not be modified.  There can be many rows for George, assuming he is issued many invoices.
Current information about George, etc.  This is updated as needed; there is one row for George.


It may be that, when issuing a new Invoice, you need to reach into the other table to update that info.  So, simply plan on always issuing two statements, preferably in the same transaction:

INSERT INTO Invoices ...;
UPDATE Current ...;   -- No harm if nothing actually changes.