update firmware via ssh? Case #19355863

Hi, I have a NV+ v2 that I have been unable to get the web interface working on for some time now. I think support is running out of ideas on what to look for short of remote access to the machine, but since I am living on a boat in Fiji without real internet access, that is not possible. I do have SSH access, so for now I start up the machine, access it via CIFS/AFP/FTP and then have to ssh into the machine to shut it down. I am fine doing that, but my partner is not a linux nerd and that is beyond what I want her to be doing.

Is there anyway either upgrade to 5.3.6 via ssh, since I can't do it via the web interface, or maybe uninstall frontview ( assume the web interface is the frontview daemon) and reinstall it via APT or something similar? I do not have 8TB of space laying around to back the machine up to do a factory install.

Thanks!