Could not find any sagem firmware to test, script should work with any creditians have minimal access to webinterface (even subscriber).
Just noticed that could not even test on those, this is v1 Amazon board, as for Danube one think going to stay with openwrt for now (not even sure it still have config partition as much as i messed with it), as for Voip wanted to try it out what you linked, but it still using vmmc and firmware, even tapidemo made router run oom once voip firmware loaded.