SBS 2003 CAL questions

Hello.

Have a 2000 Server( 15-user version) in city A and SBS 2003 (included 5-user CAL)in city B.

People in both cities use the Sharepoint on the SBS server. The 2 servers are connected via VPN tunnel, allowing users in either city to access either server.

Are the users in city A being counted as users at SBS server? When I went to the Licensing tool, it shows 5 user CAL, with maximum usage of 5. Will this prevent other users? Can I manage / view/ disconnect users on the SBS to free up other users?

Thanks in advance.

R