[ahriman]

Do you have console access, via VNC for example?

If so, download the new bsd.rd image and place it in /

Reboot, and at the boot prompt type:

boot bsd.rd

Then follow the prompts.

[h1d]

Yes, I was struggling to do this from the remote shell but I had remote access to the console to specify the ram disk to get through the upgrade process but I'd consider I'm one of the lucky ones when providers like AWS doesn't have that feature to access boot process in real time.