These are my personal notes on how to run/use OpenBSD on Ubiquiti Edgerouter, specifically for Edgerouter 4. I installed OpenBSD bunch of releases back and keep upgrading. Perhaps some of the issues highlighted below would not happen on fresher install.
The upgrade should be done one release at a time, i.e. from x.y to x.(y+1).
Note: has to be done using serial console (in order to access U-boot)