Hi,
You should not merge the snapshots into one, but rather publish each snapshot into its own distribution (and to avoid further conflicts even in a separate prefix). e.g.
- Create the debian-date and ubuntu-date snapshots
- publish the debian-date snapshot into the debian prefix
- publish the ubuntu-date snapshot into the ubuntu prefix
Right now you are mixing the debian and ubuntu distributions in the same published snapshot and are probably pulling debian packages into your ubuntu machines and vice versa.