Bleeding Edge - avanc/photOS GitHub Wiki
If you want the possibility to also install pre-release software, you have to login to your device and write OS_PRERELEASES="true"
into /data/etc/os.conf
(which usually does not exists):
> ssh root@photos-xxxxxxxx
> echo 'OS_PRERELEASES="true"' >> /data/etc/os.conf
Now, also pre-releases are shown on the webui Update page.
Find additional background information on this configuration file at https://github.com/ccrisan/thingos/wiki/os.conf