How to make & Claim the extension of time document in MSP & P6?

You need to update the time schedule , clarify the new critical path , and attach the reasons for the delay for each process on the critical path .

It depends upon the Analysis. If you are going for Time Impact Analysis, then you have to insertion or add activities indicating delays or changes into an updated schedule representing progress up to the point when a delay event occurred to determine the impact of those delay activities.

To work with the extension of time in both MSP or P6 we need to arrange the floats. changing the project duration in a effective manner is the only way to get the optimistic & effective planning.