All depends on how many total subscribers a group get. This includes the reorders. For instance, some may order just 1 or 2 groups the first time, but most of our customers order again and again, until they have gone through the list of participating publications. We also accept repeated ads. That could mean that you will run an ad for a client who is already your subscriber.
All publishers have the same chance to earn the commission for that order.
You are only paid for customers who click on your affiliate link. If they did not originate from you, your compensation is a new subscriber. You still run the ad. ClickBank take care of that and send check to you twice a month. Some of our Publishers are in this program for the new subscribers only.