==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.3.1
- Deployed with iRedMail Easy or the downloadable installer? Installer
- Linux/BSD distribution name and version: Centos 8
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MariaDB
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
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====

I'm trying to fully understand the differences between three different documentation pages.
A. https://docs.iredmail.org/sql.create.mail.alias.html
B. https://docs.iredmail.org/sql.user.mail.forwarding.html
C. https://docs.iredmail.org/user.alias.address.html

I understand these three things all do subtly different things, and I've been doing some tests with them, but I'd like to better understand the nuances / intended uses.

Process A, Create a Mail Alias Account functionally creates an account record in the "alias" table, and a corresponding entry in the "forwardings" table with the is_list boolean set.

Process B, Set Mail Forwarding creates an entry in the "forwardings" table with the is_forwarding boolean set.

Process C, User Alias Address, also creates such an entry, but with the is_alias boolean set.

So in summary, all create an entry in "forwardings", each setting a different flag, and the first also creates an entry in "alias".

My guess would be that:
- A is used to create an recipient address that is used to distribute to several existing users (what Exchange would call a Distribution List)
- B is used when you want a user to appear to be local, but they are actually on a different mail domain (e.g. john.smith@mycorp.com should appear to be part of mycorp, but is actually routed to john.smith@gmail.com)
- C is used for when a user should have two addresses for his mailbox (john.smith@... and jsmith@...)

Is this (even roughly) correct? If not, what's the difference in the way all these flags are handled?

PS: and of course there's separate subscribable mailing list capability using mlmmj, which, as I understand it, is an entirely different thing. Right?