Well, in that case..
One way or another you need to record when the first case occurs. So you have to store that information somehow. Construct isn't going to do that for you. It's not going to record every time something happens for the first time, because that could be hundreds of thousands of possible things. You have to create the logic yourself to discern when that happens.
So you can use variables to store the data that will signify when the first occurrence has happened.
You can use a group, with a local variable inside and set it to Static, and then put the events inside the group that set the variable. If it is 0, it is first occurrence, if 1 then the first occurrence has already happened.