That means you can have 20 User Manager active sessions (meaning that if User Manager is installed on the level 4 device UM as a server won't authenticate more than 20 users). You can also have 200 active users on the Hotspot (meaning that 200 users can log in, with any mixture of local accounts, accounts authenticated against a UM server, or any other RADIUS server).HotSpot active users: 200
User manager active sessions: 20