If you need to delete one of your team members, do the following:
Go to the Members section in the menu on the left of the screen.
Tap on the 3 dots icon near a team member email to open the menu.
Tap on "Revoke access to Pro".
Even when their subscrption expires, their projects saved in the app will be available on their device unless they delete them.
You will be able to restore your team member if you need this later. Also they will be able to buy their own PRO license outside of your team.