You are correct here - currently there is no workflow for removing additional leaders from callouts other than deleting the callout and re-creating it. Do you find yourself in need of this function often in your workflow?
I do not normally have to remove leaders but this one occasion I had got over enthusastic and added one extra after adding 10 others. It was a small inconvience to delete the call out and start again.
Access a broad range of knowledge to help get the most out of your products and services.