Hello,
One of the activities in my schedule had 70 days of total slack. I then realized I have to make it a predecessor of a later activity. That later activitiy was on critical path. When I assigned the later activity as a successor to the activtiy with 70 days of slack, i thought that this activity will also become critical now. But its slack not even changed and stayed at 70 days. What might be the reason? Or can this happen?