AD and Mail domains in different space name

NethServer release 7.6.1810 (final).
Good day, dear friends!
I have a domain in Win Server 2016 - @domain.local
and have a mail server on an old Linux mail server -
Users of the domain user_x@domail.local there is mail of a type without AD integration.
Is there at least some possibility to configure mail service on the new istallation of nethserver with AD integration so that users of AD user_x@domail.local could send and receive mail using the names of their boxes
I met information that it is possible to do it with UPN suffix in the AD domain, but will it work?
Are there any tricks to make the scheme work?

if it can help you …

I have a domain on AC 2019 “”, I set the suffix UPN “” and selected on “user logon name”


in Nethserver I have set its name FQDN “, joined in AC and configured the email server;
the list of users is automatically viewed in NethServer and send and receive with the name”