We don't really have a bulk addition and removal option within Teams Manager. However, it is possible to add multiple users at once.
To add users:
Navigate to the Teams tab within Teams Manager.
Find the desired team.
Click on the Members section at the bottom of the Team Card.
Enter the names of the users you'd like to add into the bar at the top (only 3 users at a time).
Click on "Add" once you're satisfied with the selection.
Since we try to avoid the possibility of human error as much as possible, and a "Remove all users" button would be a huge liability, Removal is restricted to one user at a time.
To remove users:
Navigate to the Teams tab within Teams Manager.
Find the desired team.
Click on the Members section at the bottom of the Team Card.
Hover over the user you'd like to remove.
Click the X button next to their name.
Click on "Remove" in the confirmation pop-up.
If you have a particularly large team that you'd like to restructure, we recommend either bearing with the manual process or creating it anew.