==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release):  1.5.1 MARIADB edition.
- Deployed with iRedMail Easy or the downloadable installer? Installed by script
- Linux/BSD distribution name and version: devuan chimaera (= debian bullseye)
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MariaDB (MySQL)
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
Hello. I use iredmail and I am very satisfied with it.
I decided to migrate from debian to devuan a few days ago (reason: systemd is nonsense)
I wrote the following two scripts to run iredadmin and iredapd and both work properly:
iredapd:

#!/sbin/openrc-run

name=$RC_SVCNAME
description="iRedAPD (A simple posfix policy server)"
command="/usr/bin/python3"
command_args="/opt/iredapd/iredapd.py"
pidfile="/run/iredapd.pid"

depend() {
    after net local-fs netmount 
}

iredadmin:

#!/sbin/openrc-run

name=$RC_SVCNAME
description="iRedAdmin daemon service"
supervisor="supervise-daemon"
command="/usr/bin/uwsgi"
command_args="--ini /opt/www/iredadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/iredadmin/iredadmin.pid"

start_pre () {
    ebegin "Creating working directory"
    /bin/mkdir -p /var/run/iredadmin
    ebegin "Change owner of working-dir to iredadmin:iredadmin"
    /bin/chown iredadmin:iredadmin /var/run/iredadmin
    ebegin "Change permission of working-dir to 0755"
    /bin/chmod 0755 /var/run/iredadmin
#    ebegin "Starting the daemon"
#    /usr/bin/uwsgi --ini /opt/www/iredadmin/rc_scripts/uwsgi/debian.ini --pidfile /var/run/iredadmin/iredadmin.pid
}

depend() {
    after net local-fs netmount 
}

stop() {
    ebegin "Stopping $RC_SVCNAME"
    /usr/bin/uwsgi --stop /var/run/iredadmin/iredadmin.pid
    ebegin "Remove the working directory"
    /bin/rm -rf /var/run/iredadmin
    eend $?
}

I'm having a problem right now.
I'm going to update iredadmin but the installer script gives an error: {Release version of the operating system on this server is unsupported by iRedMail}
I know devuan is not officially supported by you but I am asking for help.
Can the script be set up to think: This is a Debian?
Or is there a way to install/update iredmail without using script?

regards