My interpretation of this thread: As a worst case scenario, you are in the cockpit to fly back to home base but you found out just a new CDL is added to Tech Log Book effecting Enroute Performance Limiting weight with a penalty of 5000Kg; What I can do with this 5000kg?
JABBARRA, see the above worked example by gearpins of how easy it is to achieve this task. It is absurd to interpret the question of "how is this done?" as "how is this done if I don't have the net performance data which must by law be provided to the operator and used to accomplish this task".