Alias to parent server

SYSTEM INFORMATION
OS type and version CentOS Linux 7.9.2009
Webmin version 2.001
Virtualmin version 7.2

Hello family!
I would like to move my alias server which currently has ftp and mails users to parent server.
I began seeing " Convert Alias Server" section with the following text:
" Are you sure you want to convert this alias virtual server into a sub-server? It will no longer serve the web pages of the old target virtual server, but can have its own web content, mailboxes and mail aliases."

Is this mean will MOVE mailboxes and mail aliases to new server?
I am afraid of making a mistake

It is like I had create email and ftp users to alias server in the past. But If I test with a new temp server and alias-subserver I can’t. For that I can’t test if “Convert Alias Server” will bring emails with me