Will changing the FTP Data port config from standard to custom, for active mode, mess up existing FTP connections on port 21 using passive mode?

Working with an existing internal FTP server with (3) FTP sites where all traffic is behind my internal firewall. I now need to add a connection from an external source that is behind their own firewall. When building the FTP on the existing server I want to use a custom port, for example, of 11000. Both firewalls were modified for that connection and FTP clients can connect. BUT! No information is listed for the connection, such as file names, folders etc. I identified this as related to needing to specify a custom, active Data Port on the FTP server to allow this visibility. Ok, no issues there, I can make that happen and know how.

However, when I edit this setting on the server it looks very much to me that it would be a global effect on the entire server for all FTP sites. My concern is that if I make this change the existing connections for my internal sites will stop, even though they are using the standard port for connections.  I also have a custom FTP port (not 21 or 22) on one of my INTERNAL sites that is working fine.

Question:  Does making this change for the data port affect anything on the standard FTP port of 21? I need to make sure I won;t break my current connections by enabling this setting and specifying a port. If so, I will build another server for the external (trusted) connection.

Please advise.