Yes, you can!
DESelect admins can unassign/assign licenses to other users. The number of available licenses is based on the number of people that have the Active flag checked.
All you have to do is navigate to the Admin Panel.
On the overview screen, you can see all the available DESelect users. Select the user you want to activate/deactivate (click on the name of the user) and click on the checkbox next to Active to change their status:
Click on Save to complete.