Q: How can I designate someone to manage and schedule a team with out allowing them to change the worship flow?

A: First, make sure the person has a Planner account in your church.  Now, make the Planner a team leader (i.e. of the Ushers team). 

 Then, go to the "Settings" tab of the Ushers team, and ensure the "Leaders can create Helper accounts" is set to "Yes".  Finally, set the security level of the person to 0.