Comment # 9 on bug 1153687 from Adrian Schr�ter

concept wise I do not like this approach, since you split free text names where
there is no definition. This really works only by accident more or less.

The better way would be to replace the entire repository name, based on the
official default names as defined in OBS.

So I would recommend something like

 <default_repository_name>openSUSE_Tumbleweed</default_repository_name>

Also a

 <default_obs_url>obs://build.opensuse.org</default_obs_url>

may make sense, since in OBS the url syntax is define as 

obs://$hostname/$project/...

And having a hardcoded one breaks at least for SLE already depending on the use
case.