Whether starting a new software project or simply transitioning to agile project management, your team will need to pick a length for upcoming sprints.
Estimates are first and foremost for project planning. Eventually, as various team members get familiar with the codebase, disparities should fade away.
In response to uncertainty, team members may try to eliminate it at all costs. Doing so can consume too many resources and divert attention from real goals.
The 10-box exercise is an agile planning tool that helps the team visualize the sprint schedule and account for how the actual calendar impacts delivery.