Apologies for the months late reply and any formatting mistakes, I moved on from this and forgot about it. Either way, this doesn't seem to have been fixed in either chaemera, daedalus, or ceres (after testing in several VMs and on my laptop running Devuan). Launching the application via either the desktop or the command line (with or without polkit) still produces an error as seen by the output on my Daedalus VM:

Traceback (most recent call last):
  File "/usr/bin/software-properties-gtk", line 101, in <module>
    app = SoftwarePropertiesGtk(datadir=options.data_dir, options=options, file=file)
  File "/usr/lib/python3/dist-packages/softwareproperties/gtk/SoftwarePropertiesGtk.py", line 109, in __init__
    SoftwareProperties.__init__(self, options=options, datadir=datadir)
  File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 109, in __init__
    self.reload_sourceslist()
  File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 599, in reload_sourceslist
    self.distro.get_sources(self.sourceslist)   
  File "/usr/lib/python3/dist-packages/aptsources/distro.py", line 91, in get_sources
    raise NoDistroTemplateException(
aptsources.distro.NoDistroTemplateException: Error: could not find a distribution template for Devuan/daedalus ceres

If it helps/is related to this, running the command "distro-info --all" only seems to produce upstream Debian release names as output as seen here:

buzz
rex
bo
hamm
slink
potato
woody
sarge
etch
lenny
squeeze
wheezy
jessie
stretch
buster
bullseye
bookworm
trixie
sid
experimental

On Fri, 04 Feb 2022 01:15:30 +0000 dak@??? wrote:
>
> Version: 2.3.0+devuan2
>
> Source package python-apt-common-devuan (2.3.0+devuan2) added to Devuan suite unstable.
>
> This closes bug report 662.
>
> Thanks
>
> DAK managing the Devuan archive
>

> Format: 1.8
> Date: Fri, 04 Feb 2022 00:44:53 +0000
> Source: python-apt-common-devuan
> Architecture: source
> Version: 2.3.0+devuan2
> Distribution: unstable
> Urgency: medium
> Maintainer: Boian Bonev <> bbonev@???> >
> Changed-By: Boian Bonev <> bbonev@???> >
> Closes: 662
> Changes:
> python-apt-common-devuan (2.3.0+devuan2) unstable; urgency=medium
> .
> * Rebuild to accommodate changes in distro-info-data (Closes: #662)
> Checksums-Sha1:
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> 7e5eed6c2de4b89f4dae75df66d15beb9287314c 4172 python-apt-common-devuan_2.3.0+devuan2.tar.xz
> 3cefa49223c8d31e32640f0e9845a15a7e658cca 6730 python-apt-common-devuan_2.3.0+devuan2_source.buildinfo
> Checksums-Sha256:
> 0a50a0fb81a95c6752a964aae467960835a3258f566bd22627008cc53750476e 1374 python-apt-common-devuan_2.3.0+devuan2.dsc
> 7c71397e6c8b09bf3f47996d0b413e41aa1bd7f01b51db374c75d3baf2db80ff 4172 python-apt-common-devuan_2.3.0+devuan2.tar.xz
> db644ba0ec109536340e5d42c9de975a0ecee38b545b1f92e73e9e08f7e982ec 6730 python-apt-common-devuan_2.3.0+devuan2_source.buildinfo
> Files:
> 74114fee3aca0c1478e792c497e44a87 1374 python optional python-apt-common-devuan_2.3.0+devuan2.dsc
> a2ae69804f78ff4d865ff3319bf1b752 4172 python optional python-apt-common-devuan_2.3.0+devuan2.tar.xz
> c295b2d38cfcbcc2ebe4cd409ffccc32 6730 python optional python-apt-common-devuan_2.3.0+devuan2_source.buildinfo
>
>