WorshipPlanning.com can help team leaders find substitutes for roles assignments that have been declined. When a person's assignment status is Decline there will appear a "subs" link under their name on the page where people are scheduled.  Click this link and WP will open a window showing a list of available team members that are probably candidates for replacements. This list is also found in any Decline emails that are sent to team leaders as a part of assignment response notification emails.

You can also find a list of qualified people to fill an empty role by clicking on the "No Person" link next to the role name that is scheduled for the service.

The list of potential candidates is generated based on several factors, such as: availability, if the person has served in that role before, if the person has that as their default role, and if the person has that listed as a skill. Using these factors, WP scores each team member and lists them, starting with the most qualified (according to the scores).