We are a small shop with only 8 agents. All agents are set with a with a rank of 1. Take the following scenario.
We open at 8:00AM. By 9:00AM all agents have handled 10 calls. One agent goes on break at 9:00AM for 30 minutes. When she returns at 9:30, all other agents have taken 15 calls. As soon as the agent that was on marks themself as available, they get the next 5 calls that comes into the queue (to get her to 15 calls). After that 5th call she takes, the calls start to rotate the agents again.