Even with connection timeout set to 60 seconds, connection times out at 21 seconds

Even with timeout set to 60 seconds, when trying to connect, after 21 seconds, log shows "A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond."

Can the 21 second limit be changed on my side to wait longer for the connected party to respond?

Are you sure the problem is due to too "short" timeout?
If you use another FTP client, can it connect, if it waits longer than 20 seconds?