It was a big concern of mine too, actually you had motivated me to look into flashing custom Armbian and I made a guide for getting it working even through GPIO.
But that's kind of pointless now, especially since 'Futurebit OS' is actually Armbian too. Just wanted to point that out since from your message it appears that you think they're running Ubuntu.
As far as I know, Armbian is the only distro you can get precompiled for the Orange Pi 4 online.
I'm not sure why people think its ubuntu either. I have had a lot hate relationship with my apollos but more love now these things just run and run and run and run. When you make a purchase and you get exactly what you bought and it works thumbs up futurebit and the giants behind all of this.
futurebit@futurebitbtc:~$ cat /etc/os-release
NAME="Ubuntu"
VERSION="20.04.4 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Armbian 22.08.0-trunk Focal"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal
futurebit@futurebitbtc:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.4 LTS
Release: 20.04
Codename: focal
futurebit@futurebitbtc:~$ uname -r
5.15.57-rockchip64