I downloaded the most fresh image Armbian_21.02.3_Orangepipc_focal_current_5.10.12_desktop.img.xz from armbian.com for my board OrangePi PC. I installed it and had a problem with a process lightdm-gtk-greeter which eats 100% of CPU all time after first board reboot. Updating via apt-get update/upgrade didn't solve the problem. First of all i tried to find the solution in the internet and in this site, but all solutions which i found didn't help me. The most close topic for other board is here.
Also i tried to run archived versions:
Armbian_21.02.1_Orangepipc_focal_current_5.10.12_desktop.img.xz - had same issue.
Armbian_20.08.1_Orangepipc_focal_current_5.8.5_desktop.img.xz - didn't have same issue.
I think that all Armbian_21.XX.X for OrangePi PC had this issue, but i didn't check all.
After i found that 20.08.1 didn't have issue with lightdm , i updated it as usual:
sudo apt-get update
sudo apt-get upgrade
And this fixed my issue, now i have Armbian_21.02.3 which works fine.
Hope this post help somebody and developers will fix this issue next time.
Good luck.