Maybe the misunderstanding / confusing thing about this
for you (@chrisse ) is, that this beta state and than stable / factory image availability for a new release is not the same as CalyxOS official support for the Fairphone (which would mean an official page with download links etc. … e.g. the same thing the Lineage users wait for).
You always have to search for the factory image (link) on your own or put it together manually (or wait until @hirnsushi is so kind again and post it here). This topic was discussed here: Howto install Calyx OS on FP4 - #39 by Smojo