Interpretation of The Difference between The Impacted and The Updated Schedule
A delay event was modeled/inserted into an agreed upon schedule which was updated just before the delay event’s start date; this exercise has resulted in giving a new project completion date (say 10 days later). However, the subsequent (regular) schedule update which reflects the Contractor’s actual progress (say “data date” is one month later than the impacted one) is showing new project completion date equals to 15 days later.
In the above scenario we can see that:
The impacted schedule (at the beginning of the Window) gives a delay of 10 days