==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.7.2
- Deployed with iRedMail Easy or the downloadable installer? Downloadable installer
- Linux/BSD distribution name and version: Rocky Linux 8
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):  MariaDB
- Web server (Apache or Nginx): Apache2
- Manage mail accounts with iRedAdmin-Pro? Yes
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Under domains and accounts > selected domain > relay I can specify in/out relay but I cannot select the "relay without verifying local recipients" option. I check it and save but it becomes deselected.

I am preparing to migrate accounts from third party server into local iredmail server, need to prepare the server by adding the domain, mailboxes, aliases, and sync the mail from the live third-party server into the iredmail server without impacting mailflow until the cutover date.

I almost have this done, when I send an email to a mailbox that is to be migrated, and the mailbox exists locally, the relay is used and the email ends up in the mailbox on the third-party server. However, when I email an alias or mailbox that I do not have locally, the relay is not used, a bounce is issued.

Do I need to do something to get the "relay without verifying local recipients" option to work and or do you have a suggestion on how to handle migrations into iredmail like this?

I plan to use imapsync to do the actual email migration.

Thanks!