If you don't make a post in each activity period then you'll lose out on that activity forever. You can't just abandon your account and when you come back expect to collect all the activity points as that's not how the activity system works. In fact, it was designed to stop people from doing that as by its very name it is a measure of how active you have been here, not just how long you have been registered.
I see. Didn't intend on going inactive then come back to farm all those activity points. I was just trying to figure out how activity system works. If having a day job and studying seems to be easy then I can stay on here longer but that isn't case. Thanks for clarifying.